Form 6-K

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                        Report of Foreign Private Issuer

                        Pursuant to Rule 13a-16 or 15d-16
                     of the Securities Exchange Act of 1934

                          For the month of March, 2006

                              CONVERIUM HOLDING AG
                  ---------------------------------------------
                 (Translation of registrant's name into English)
                                 Baarerstrasse 8
                                   CH-6300 Zug
                                   Switzerland
                     --------------------------------------
                    (Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports
under cover Form 20-F or Form 40-F.

                     Form 20-F   X           Form 40-F
                              -------                 -------

Indicate by check mark whether the registrant by furnishing the information
contained in this Form is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

                           Yes                No   X
                              -------           -------

If "Yes" is marked, indicate the file number assigned to the registrant in
connection with Rule 12g3-2(b):  82-   Not Applicable

                                                                               1


                           Converium Holding Ltd, Zug


Zug,  Switzerland  - March 15, 2006 -  Converium  reports net income of US$ 68.7
million for the full year 2005.

In the  financial  year  2005  Converium  has  produced  net  income of US$ 68.7
million. This result primarily reflects:

     o    a  satisfactory   underwriting   performance  of  Converium's  ongoing
          operations,  which  produced  total  segments'  income  of  US$  173.8
          million;

     o    a net pre-tax  impact of US$ 164.8  million from the  following  major
          natural  catastrophes:  winter storm Erwin,  the Continental  European
          floods and hurricanes Katrina, Rita and Wilma;

     o    a net positive impact of prior accident years on the technical  result
          of US$ 12.1 million,  mainly due to the  continuing  stabilization  of
          Converium's prior accident years' loss reserves;

     o    the  successful   progression  of  the  Converium  Reinsurance  (North
          America) Inc. (CRNA) run-off and commutation strategy,  which resulted
          in a total  reduction  of net  liabilities  of US$  653.1  million  to
          approximately  US$  1.1  billion,   and  a  net  income  benefit  from
          commutations of US$ 60.5 million.

     o    total operating and  administration  expenses of US$ 210.8 million,  a
          decline of 4.1% compared  with 2004,  despite  significant  additional
          expenses arising from the internal review and restatement,  as well as
          Converium's operational restructuring; and

     o    a total  investment  result of US$ 350.4 million,  or an average total
          investment income yield of 4.4%, which is equal to 2004.


For the fourth quarter of 2005 Converium reports net income of US$ 34.2 million,
largely driven by:

     o    a  satisfactory   underwriting   performance  of  Converium's  ongoing
          operations, which produced total segments' income of US$ 63.2 million;

     o    hurricane  Wilma,  which  caused  net  pre-tax  losses  for the entire
          Company of approximately US$ 46.5 million;

     o    operating   and   administration   expenses   of  US$  63.2   million,
          representing  an increase of US$ 22.9 million  compared with the third
          quarter  of  2005,  primarily  due to  expenses  associated  with  the
          internal review and the restatement;

     o    successful  commutations of CRNA liabilities resulting in a net income
          benefit of US$ 22.0 million; and

     o    a  total  investment  result  of  US$  111.6  million  or  an  average
          annualized  total  investment  income  yield  of 6.0%,  including  net
          realized capital gains of US$ 33.6 million, primarily from the sale of
          equity securities.


Based on  Converium's  financial  performance  in 2005 and the Company's  strong
capitalization,  the Board of  Directors  proposes a gross cash  dividend of CHF
0.10 per share to the Annual General Meeting of April 11, 2006.

Inga Beale, Chief Executive  Officer,  commented:  "The unprecedented  string of
natural catastrophes experienced in 2005 has served as a reminder that we are in
the business of risk.  Nevertheless  I am  encouraged by  Converium's  financial
results for 2005. Based on the underlying  quality of our ongoing business,  the
stability of prior accident years' loss reserves and the progress in running-off
and  commuting  CRNA  liabilities,  we  have  been  able to  absorb  significant
catastrophe losses and to generate net income of close to US$ 70 million."

Inga Beale  continued:  "After my first six weeks at the helm of  Converium I am
convinced that our franchise is stable,  our business  strategy  appropriate and
our  underwriting  expertise top class. I therefore  strongly  believe that 2006
will see further progress towards Converium's sustainable recovery."

                                                                               2


Financial results of the fourth quarter and the full year 2005

Key metrics (in US$, unless noted)


                                                                                   
                                                                  Three months ended      Full year 2005
                                                                   December 31, 2005

o    Gross premiums written                                            375.4 million     1,994.3 million
o    Income before tax                                                  38.8 million        84.3 million
o    Pre-tax operating income                                            2.8 million      U100.8 million
o    Ongoing total segment income(1)                                    63.2 million       173.8 million
o    Impact from winter storm Erwin, Continental European floods        60.4 million       164.8 million
     and hurricanes Katrina, Rita and Wilma
o    Net income                                                         34.2 million        68.7 million
o    Ongoing non-life combined ratio(2)                                       110.8%              107.2%
o    Impact on combined ratio from winter storm Erwin, European             14.9 pts             7.7 pts
     floods and hurricanes Katrina, Rita and Wilma
o    Adjusted ongoing non-life combined ratio (excluding Erwin,                95.9%               99.5%
     floods and hurricanes)
o    Average annualized total investment income yield (pre-tax)                 6.0%                4.4%
o    Shareholders' equity                                                                1,653.4 million



For the full year 2005, Converium reported pre-tax operating income of US$ 100.8
million  and net income of US$ 68.7  million.  This  result  reflects a negative
impact of US$ 164.8  million  from the  following  major  natural  catastrophes:
winter storm Erwin, the Continental  European floods and the hurricanes Katrina,
Rita and Wilma. However, the financial performance benefited from a net positive
impact of prior  accident  years on the  technical  result  of US$ 12.1  million
resulting from net positive  development of prior accident  years' loss reserves
of US$ 75.5  million,  offset by  reductions  in  premiums,  related  losses and
acquisition  costs of net US$ 63.4  million.  Additional  positive  effects were
recorded due to the successful progression of the CRNA run-off and the effective
execution of its  commutation  strategy.  Converium also reported a satisfactory
underwriting performance of its ongoing operations, which produced total segment
income of US$ 173.8  million.  The ongoing  non-life  combined ratio was 107.2%.
Finally,  the full year performance  benefited from a decline in total operating
and  administration  expenses  by 4.1% to US$  210.8  million  in 2005 - despite
significant additional legal, audit and consulting expenses, mainly arising from
the internal  review and  restatement of prior years'  financial  information as
well as the Company's operational restructuring.

In 2005,  gross premiums  written  decreased by 49.9%,  net premiums  written by
51.3% and net premiums  earned by 38.6%.  This decline in gross and net premiums
written  reflects the  reduction in overall  business  volume due to the ratings
downgrades  in 2004 and the  placement  of CRNA into orderly  run-off.  Overall,
full-year gross premiums written are closely in line with the previously  stated
volume expectation of approximately US$ 2 billion.


-------------------------------------
(1)  Total segment  income  (loss) is defined as net premiums  earned plus total
     investment   results  minus  losses,   loss  expenses  and  life  benefits,
     acquisition costs and other operating and administration expenses.

(2)  Ongoing  non-life  combined  ratio is  defined as  non-life  loss ratio (to
     premiums earned) plus non-life  acqusition costs ratio (to premiums earned)
     plus non-life administration expense ratio (to premiums written).

                                                                               3


Based  on  the  developments  of  2004,  Converium  placed  its  North  American
reinsurance  operations  into  run-off  and started to  implement  and execute a
vigorous  commutation  strategy.  In 2005,  CRNA commuted net liabilities of US$
372.9 million. As a result,  total net liabilities of CRNA decreased by 36.9% to
approximately US$ 1.1 billion. Based on the commutations a net income benefit of
US$ 60.5 million was recorded.

Converium  reported an ongoing  non-life  combined  ratio of 107.2% for the full
year 2005, as compared with 106.1% for 2004. Adjusted for the losses from winter
storm Erwin, the Continental European floods as well as hurricanes Katrina, Rita
and Wilma,  the ongoing  non-life  combined  ratio was 99.5%,  which  reflects a
satisfactory underlying underwriting performance.

The  Life & Health  Reinsurance  segment  reported  segment  income  of US$ 17.6
million for the year ended  December 31, 2005, as compared with US$ 16.7 million
for the previous year.

Converium  reported net  investment  income for 2005 of US$ 324.9 million and an
average net investment  income yield of 4.1%, an increase as compared with 2004.
This  improvement was achieved  despite a lower asset base and largely  resulted
from a higher allocation to fixed maturities  securities.  The Company's average
total  investment  income yield for the year ended  December  31, 2005  remained
unchanged at 4.4% compared with 2004 and reflects net realized  capital gains of
US$ 25.5 million, which occurred primarily in the fourth quarter of 2005.

For the fourth quarter of 2005,  Converium  reported pre-tax operating income of
US$ 2.8 million and a net income of US$ 34.2 million.  The quarterly  result was
largely driven by a total impact from natural  catastrophes of US$ 60.4 million.
Hurricane Wilma  accounted for US$ 46.5 million,  with the residual impact being
attributable to further  developments for hurricanes Katrina and Rita, offset by
loss  reserve  reductions  relating  to the 2004 Asian  tsunami.  The  financial
performance  of the fourth  quarter of 2005 was also  impacted by operating  and
administration  expenses of US$ 63.2  million,  representing  an increase of US$
22.9  million  compared  with the third  quarter of 2005.  This  development  is
reflective of  extraordinary  legal,  audit and consulting fees of approximately
US$ 15 million mainly associated with the internal review and the restatement of
prior years' financial accounts.

The negative  effects from natural  catastrophes  and  increasing  operating and
administration  expenses were partially offset by a net positive impact of prior
accident  years on the technical  result of US$ 6.8 million  resulting  from net
positive development of prior accident years' loss reserves of US$ 31.9 million,
and premiums,  related losses and acquisition costs of net US$ 25.1 million.  In
addition,  a net income  benefit of US$ 22.0 million was recorded as a result of
the successful  commutation of CRNA liabilities.  The performance of Converium's
ongoing operations is reflected in total segment income of US$ 63.2 million.

Gross  premiums  written in the fourth quarter of 2005 decreased by 13.6% to US$
375.4  million,  net  premiums  written  by 15.2% to US$ 314.5  million  and net
premiums earned by 35.5% to US$ 441.5 million,  as compared with the same period
in 2004. These decreases in premiums are largely due to the rating downgrades in
2004 and the placement of CRNA into orderly run-off.

For the fourth quarter of 2005,  Converium reported net investment income of US$
78.0 million and an average  annualized net  investment  income yield of 4.2%, a
slight increase as compared with 2004. The Company's  average  annualized  total
investment  income yield was 6.0%, as compared to 4.3% in the fourth  quarter of
2004. This is a result of net realized capital gains of US$ 33.6 million.


Outlook

The continuing  resilience of Converium's  franchise as evidenced in the January
renewals as well as the improving  financial  performance  demonstrates that the
Company's  current  business  strategy  is a promising  basis for a  sustainable
recovery.

Based on the successful January renewals and barring any exceptional catastrophe
losses,  adverse  financial  markets  developments or other  unexpected  adverse
developments,  Converium expects a further  improvement of its financial results
in 2006.

                                                                               4


Business Development

The  following  are comments on the  development  of  Converium's  three ongoing
business  segments,  the Run-Off segment and the Corporate Center.  Reference is
made to the tables attached to this press release.

Standard  Property & Casualty  Reinsurance  represented  approximately  40.7% of
total net  premiums  written  in 2005.  For the full  year  2005 and the  fourth
quarter  the  Standard  Property &  Casualty  Reinsurance  segment of  Converium
reported segment income of US$ 46.7 million and US$ 24.0 million,  respectively.
For the same periods of 2004 the segment reported income of US$ 91.5 million and
a loss of US$ 29.4, respectively.

The  positive  segment  result in 2005 was  achieved  despite a string of severe
natural catastrophe losses,  reflecting the quality of the segment's  underlying
book of  business.  The  combined  ratio for the full year 2005 was  109.5%,  as
compared with 101.6% in 2004. The headline  losses in 2005 added 15.4 percentage
points to the segment's combined ratio:  winter storm Erwin (US$ 32.5 million or
3.7 percentage points), the Continental European floods (US$ 24.8 million or 2.8
percentage  points),  hurricane  Katrina  (US$ 25.6  million  or 2.9  percentage
points),  hurricane  Rita  (US$  11.2  million  or 1.3  percentage  points)  and
hurricane Wilma (US$ 41.6 million or 4.7 percentage  points).  In addition,  the
segment's combined ratio reflects an increased  administration expense ratio due
to the  reduced  premium  volume in 2005.  For the fourth  quarter of 2005,  the
Standard  Property & Casualty  Reinsurance  segment reported a combined ratio of
116.4%,  which  includes an impact of 25.8  percentage  points due to  hurricane
Wilma and 3.4  percentage  points  relating to  additional  claims for hurricane
Katrina.  The combined ratio for the fourth quarter of 2005 compares with 124.4%
for the same period of 2004.

The segment's 2005 result benefited from a net positive impact of prior accident
years on the technical  result of US$ 19.7 million  resulting  from net positive
development of prior accident  years' loss reserves of US$ 30.7 million,  offset
by reductions in premiums,  related losses and acquisition costs of net US$ 11.0
million.  The largest developments in prior accident years' loss reserves relate
to property (net positive  development of US$ 73.3 million),  motor (net adverse
development of US$ 25.0 million) and general third party  liability (net adverse
development of US$ 23.4  million).  For the fourth quarter of 2005, the Standard
Property & Casualty  Reinsurance segment recorded a net positive impact of prior
accident  years on the technical  result of US$ 8.1 million  resulting  from net
positive development of prior accident years' loss reserves of US$ 21.0 million,
offset by reductions in premiums,  related losses and  acquisition  costs of net
US$ 12.9 million.

For the year ended December 31, 2005, gross premiums written  decreased by 46.8%
to US$ 803.1 million, net premiums written by 46.4% to US$ 739.0 million and net
premiums  earned by 36.7% to US$ 880.8 million.  In general,  premium volume was
impacted by the ratings  downgrades in 2004,  the placement of CRNA into orderly
run-off as well as by the decision to reduce writings for profitability reasons.
More specifically,  for the full year 2005 the reduction in net premiums written
in the  Standard  Property & Casualty  Reinsurance  segment by line of  business
included:

     o    Motor, which decreased by 56.9% to US$ 188.4 million;

     o    Property, which declined by 25.8% to US$ 390.6 million;

     o    General  third  party  liability,  which  went down 61.3% to US$ 146.7
          million; and

     o    Personal accident (assumed from non-life insurers), which decreased by
          61.4% to US$ 13.3 million.

For the fourth quarter of 2005, gross premiums written decreased by 58.7% to US$
92.1 million, net premiums written by 53.3% to US$ 77.8 million and net premiums
earned by 39.8% to US$ 161.4 million.


Specialty Lines represented approximately 40.6% of total net premiums written in
2005. For the full year 2005 and the fourth quarter, the Specialty Lines segment
of Converium  reported segment income of US$ 109.5 million and US$ 32.6 million,
respectively.  This performance  compares with segment losses of US$ 7.3 million
and US$ 41.8 million for the respective periods of 2004.

The segment's combined ratio for the full year 2005 was 105.4%, as compared with
110.6% in 2004. In 2005, the segment's  performance was negatively affected by a
total net pre-tax impact of US$ 13.5 million of losses from hurricanes  Katrina,
Wilma and Rita. For the fourth quarter of 2005, the segment  reported a combined
ratio of 108.4%,  as  compared  with  118.3% for the same  period of 2004.  This
positive  trend was offset by an increased  administration  expense ratio due to
the reduced  premium  volume in 2005 as well as the fronting  commission for the
business written through Global Aerospace Underwriting Managers Ltd. (GAUM).

                                                                               5


The  segment's  result in 2005  benefited  from a net  positive  impact of prior
accident  years on the technical  result of US$ 23.1 million  resulting from net
positive development of prior accident years' loss reserves of US$ 55.3 million,
offset by reductions in premiums,  related losses and  acquisition  costs of net
US$ 32.2  million.  The  largest  developments  in prior  accident  years'  loss
reserves  related to aviation & space (US$ 41.6  million).  They were  partially
offset  by  smaller  net  adverse  developments  in the  workers'  compensation,
engineering  and marine & energy  lines of business.  For the fourth  quarter of
2005,  the  Specialty  Lines  segment  recorded a net  positive  impact of prior
accident  years on the technical  result of US$ 3.7 million  resulting  from net
positive  development of prior accident years' loss reserves of US$ 7.7 million,
offset by premiums, related losses and acquisition costs of net US$ 4.0 million.

For the year ended December 31, 2005,  gross  premiums  written in the Specialty
Lines  segment  decreased by 49.7% to US$ 833.1  million,  net premiums  written
declined by 52.9% to US$ 737.7 million and net premiums earned declined by 23.7%
to US$ 1,059.2  million.  This development is due to the lowering of Converium's
financial  strength  ratings  in 2004 and the  placement  of CRNA  into  orderly
run-off. More specifically, it reflects:

     o    Aviation & space,  which  decreased by 40.2% to US$ 241.8  million;  o
          Credit & surety, which fell by 71.4% to US$ 58.4 million;

     o    Professional liability and other special liability,  which declined by
          35.2% to US$ 282.8 million;

     o    Engineering, which decreased by 41.6% to US$ 65.5 million; and

     o    Marine & energy, which declined by 22.4% to US$ 64.0 million.

These  decreases in net  premiums  written  were  partially  offset by growth in
agribusiness,  where  net  premiums  written  increased  by  221.9%  to US$ 36.7
million,  reflecting the success of Converium's  strategy to expand this line of
business  in Europe.  In the  fourth  quarter  of 2005  gross  premiums  written
decreased by 53.7% to US$ 239.5  million,  net premiums  written by 60.7% to US$
195.7  million and net premiums  earned by 47.6% to US$ 215.3 million due to the
ratings downgrades in 2004 and the placement of CRNA into orderly run-off.


Life & Health Reinsurance represented  approximately 16.9% of total net premiums
written  in 2005.  For the full year  2005 and the  fourth  quarter,  the Life &
Health  Reinsurance  segment of Converium  reported  segment  income of US$ 17.6
million and US$ 6.6 million, respectively, as compared with US$ 16.7 million and
US$ 5.8 million, respectively, in the same periods of 2004. The segment reported
a  technical  result for the full year 2005 and the  fourth  quarter of US$ 14.2
million and US$ 1.3 million, respectively, as compared with US$ 16.4 million and
US$ 6.1  million  in the  previous  year.  Technical  result is  defined  as net
premiums earned minus losses,  loss expenses and life benefits minus acquisition
costs plus other technical income,  mainly technical  interest.

The decrease in the technical  result during 2005 was primarily  attributable to
Converium's  decision  to  cancel  existing  reinsurance  transactions  in Latin
America and the establishment of an additional  provision for the Asian tsunami.

For the year ended  December  31,  2005,  gross  premiums  written in the Life &
Health Reinsurance segment decreased by 2.8% to US$ 318.8 million,  net premiums
written  by 2.2% to US$ 306.4  million  and net  premiums  earned by 1.2% to US$
314.8  million.  The reductions  occurred  mainly in the health line of business
which  contracted  by 30.8%  to US$  23.1  million,  primarily  attributable  to
Converium's  decision to cancel existing business in the Middle East in 2004. In
the fourth  quarter of 2005,  gross premiums  written  decreased by 12.7% to US$
55.0 million, net premiums written declined by 27.8% to US$ 53.0 million and net
premiums  earned fell by 24.1% to US$ 71.6 million.  The reduced premium volumes
were mainly  driven by the update of  underlying  information  for the actuarial
calculations of financing treaties.

                                                                               6


The  Run-Off  segment  reported  segment  income  for the full year 2005 and the
fourth  quarter  of US$ 47.6  million  and US$ 15.0  million,  respectively,  as
compared with a segment loss of US$ 296.0 million and segment income of US$ 87.8
million for the same periods of 2004.

For the full year 2005, the segment result was negatively affected by hurricanes
Katrina,  Rita and Wilma with a total net impact of US$ 15.6  million in losses,
offset by a net income  benefit of US$ 60.5  million from  commutations.  In the
fourth  quarter,  CRNA  commuted net  liabilities  of US$ 141.4  million,  which
resulted in a net income benefit of US$ 22.0 million.

For the full year 2005 the  Run-Off  segment  recorded a net  adverse  impact of
prior accident years on the technical result of US$ 30.7 million  resulting from
net adverse  development  of prior  accident  years'  loss  reserves of US$ 10.5
million and reductions in premiums,  related losses and acquisition costs of net
US$ 20.2 million. For the fourth quarter of 2005, the Run-Off segment recorded a
net adverse impact of prior  accident  years on the technical  result of US$ 5.0
million, with no significant underlying movements.

The Corporate Center carries certain  administration  expenses such as the costs
of the Board of Directors,  the Global Executive Committee,  and other corporate
functions as well as other expenses not allocated to the operating segments. For
the full year 2005 and the fourth quarter, operating and administration expenses
were US$ 50.1 million and US$ 22.8 million,  respectively,  as compared with US$
38.2 million and US$ 12.7 million for the same periods of 2004.  The increase in
2005 was  mainly  due to  extraordinary  legal,  audit  and  consulting  fees of
approximately  US$ 15  million,  mainly  related  to  the  internal  review  and
restatement of prior years' financial accounts in the fourth quarter of 2005.

                                                                               7




                                                                     
Financial highlights: Income statement,          Three months ended    Year ended
return on equity                                     December 31,     December 31,

                                                   2005     2004         2005     2004
In US$ million, unless noted                               restated             restated
----------------------------                     --------  --------   --------  --------
Gross premiums written                              375.4     434.5    1,994.3   3,978.7
-  change (%)                                      -13.6%               -49.9%
----------------------------------------------------------------------------------------
Net premiums written                                314.5     370.8    1,815.7   3,726.1
-  change (%)                                      -15.2%               -51.3%
----------------------------------------------------------------------------------------
Net premiums earned                                 441.5     684.6    2,383.2   3,882.2
-  change (%)                                      -35.5%               -38.6%
----------------------------------------------------------------------------------------
Ongoing non-life loss ratio(3)                      68.8%     83.1%      77.4%     77.6%
-  change in percentage points                    -14.3pts             -0.2pts
----------------------------------------------------------------------------------------
Ongoing non-life acquisition costs ratio(4)         33.8%     32.5%      22.9%     24.5%
-  change in percentage points                    +1.3pts              -1.6pts
----------------------------------------------------------------------------------------
Ongoing non-life administration expense ratio(5)     8.2%      4.6%       6.9%      4.0%
-  change in percentage points                    +3.6pts              +2.9pts
----------------------------------------------------------------------------------------
Ongoing non-life combined ratio(6)                 110.8%    120.2%     107.2%    106.1%
-  change in percentage points                    -9.4pts              +1.1pts
----------------------------------------------------------------------------------------
Life & Health technical result(7)                     1.3       6.1       14.2      16.4
-  change (%)                                      -78.7%               -13.4%
----------------------------------------------------------------------------------------
Total investment result(8)                          111.6      89.1      350.4     359.2
-  change (%)                                      +25.3%                -2.4%
----------------------------------------------------------------------------------------
Average total investment income yield(9)             6.0%      4.3%       4.4%      4.4%
-  change in percentage points                    +1.7pts                    -
----------------------------------------------------------------------------------------
Total investment return(10)                          54.9     110.0      312.0     334.1
-  change (%)                                      -50.1%                -6.6%
----------------------------------------------------------------------------------------
Pre-tax operating income (loss)(11)                   2.8      -2.0      100.8    -321.1
-  change (%)                                        n.m.                 n.m.
----------------------------------------------------------------------------------------
Net income (loss)                                    34.2      10.9       68.7    -582.5
-  change (%)                                     +213.8%                 n.m.
----------------------------------------------------------------------------------------
Basic earnings (loss) per share (US$)                0.23      0.08       0.47     -9.19
- change (%)                                      +187.5%                 n.m.
----------------------------------------------------------------------------------------
Return on equity(12)                                 8.1%      3.5%       4.0%    -30.2%
- change in percentage points                     +4.6pts                 n.m.
----------------------------------------------------------------------------------------


-------------------------------------

(3)  Ongoing  non-life loss ratio is defined as losses and loss expenses divided
     by net premiums earned.

(4)  Ongoing non-life  acquisition  costs ratio is defined as acquisition  costs
     divided by net premiums earned.

(5)  Ongoing non-life administration expense ratio is defined as other operating
     and  administration  expenses  divided by net premiums  written,  excluding
     Corporate Center segment expenses.

(6)  Ongoing  non-life  combined  ratio is  defined as  non-life  loss ratio (to
     premiums earned) plus non-life acquisition costs ratio (to premiums earned)
     plus non-life administration expense ratio (to premiums written).

(7)  Life & Health  technical  result is defined as net  premiums  earned  minus
     losses,  loss expenses and life benefits minus acquisition costs plus other
     technical income, mainly technical interest.

(8)  Total  investment  result is  defined  as net  investment  income  plus net
     realized capital gains (losses).

(9)  Average total investment  income yield is defined as net investment  income
     plus net realized  capital gains (losses) divided by average total invested
     assets  (including cash and cash  equivalents),  pre-tax and annualized for
     quarterly yield.

(10) Total  investment  return is  defined  as net  investment  income  plus net
     realized capital gains (losses) plus change in net unrealized capital gains
     (losses) divided by average total invested assets  (including cash and cash
     equivalents), pre-tax and annualized for the quarterly yield.

(11) Pre-tax  operating  income  (loss) is  defined  as  pre-tax  (loss)  income
     excluding  pre-tax net  realized  capital  gains  (losses),  impairment  of
     goodwill, amortization of intangible assets and restructuring costs.

(12) Return on equity is  defined as net (loss)  income  (after-tax)  divided by
     shareholders'  equity at the  beginning of the period,  annualized  for the
     quarterly return on equity.

                                                                               8


Financial highlights: Balance sheet              Dec. 31,       Dec. 31,
                                                   2005          2004
In US$ million, unless noted                                   restated
---------------------------------------------------------------------------
Total invested assets plus cash                   7,281.6       8,467.1
-  change (%)                                      -14.0%
---------------------------------------------------------------------------
Claims supporting capital(13)                     2,044.6       2,125.9
-  change (%)                                       -3.8%
---------------------------------------------------------------------------
Shareholders' equity                              1,653.4       1,734.8
-  change (%)                                       -4.7%
---------------------------------------------------------------------------
Book value per share (US$)(14)                      11.29         11.86
-  change (%)                                       -4.8%
---------------------------------------------------------------------------
Book value per share (CHF)(14)                      14.88         13.49
-  change (%)                                      +10.3%
---------------------------------------------------------------------------



                                                                     
Financial highlights: Investment results         Three months ended      Year ended
                                                     December 31,       December 31,

                                                   2005      2004       2005      2004
In US$ million, unless noted                               restated             restated
----------------------------                     --------  --------   --------  --------
Investment income - Fixed maturities                 51.3     54.9       221.3     198.3
----------------------------------------------------------------------------------------
Investment income - Equity securities                 1.1       1.6        5.9      14.8
----------------------------------------------------------------------------------------
Investment income - Funds Withheld Asset             14.3      17.6       62.6      75.1
----------------------------------------------------------------------------------------
Other investment income, net                         11.3      10.5       35.1      24.5
----------------------------------------------------------------------------------------
Net investment income                                78.0      84.6      324.9     312.7
----------------------------------------------------------------------------------------
Average net investment income yield (pre-tax)       4.2%*     4.1%*       4.1%      3.8%
----------------------------------------------------------------------------------------

Net realized capital gains (losses)                  33.6       4.5       25.5      46.5
----------------------------------------------------------------------------------------
Total investment result                             111.6      89.1      350.4     359.2
----------------------------------------------------------------------------------------
Average total investment income yield (pre-tax)     6.0%*     4.3%*       4.4%      4.4%
----------------------------------------------------------------------------------------

Change in net unrealized (losses) gains (pre-tax)   -56.7      20.9      -38.4     -25.1
----------------------------------------------------------------------------------------
Total investment return (pre-tax)                    54.9     110.0      312.0     334.1
----------------------------------------------------------------------------------------
Average total investment return (pre-tax)                                 4.0%      4.1%
----------------------------------------------------------------------------------------
Average total invested assets (including cash     7,443.8   8,215.1    7,874.4   8,125.0
and cash equivalents)
----------------------------------------------------------------------------------------



*   These figures are presented on an annualized basis


-------------------------------------
(13) Claims supporting capital is defined as total equity plus debt.

(14) Reflects the impacts of the Rights  Offering that occurred in October 2004.

                                                                               9



The company has made it a policy not to provide any quarterly or annual earnings
guidance and it will not update any past outlook for full year earnings. It will
however provide investors with perspectives  selected on its value drivers,  its
strategic  initiatives and those factors critical to understanding  its business
and operating environment and certain financial guidance.



Enquiries

Esther Gerster                                      Zuzana Drozd
Head of Public Relations                            Head of Investor Relations

esther.gerster@converium.com                        zuzana.drozd@converium.com

Phone:  +41 (0) 44 639 90 22                        Phone:  +41 (0) 44 639 91 20
Fax:    +41 (0) 44 639 70 22                        Fax:    +41 (0) 44 639 71 20


About Converium

Converium is an independent  international  multi-line  reinsurer  known for its
innovation,  professionalism  and service.  Today  Converium  employs  about 600
people  in 18  offices  around  the globe and is  organized  into four  business
segments:  Standard Property & Casualty Reinsurance,  Specialty Lines and Life &
Health  Reinsurance,  which are based  principally  on ongoing  global  lines of
business, as well as the Run-Off segment, which primarily comprises the business
from Converium  Reinsurance  (North  America) Inc.,  excluding the US originated
aviation business portfolio. Converium has a "BBB+" rating (outlook stable) from
Standard & Poor's and a "B++" rating (outlook stable) from A.M. Best Company.


                                  * * * * * * *

                                                                              10


Important Disclaimer

This document contains  forward-looking  statements as defined in the US Private
Securities Litigation Reform Act of 1995. It contains forward-looking statements
and  information  relating  to the  Company's  financial  condition,  results of
operations,   business,   strategy  and  plans,  based  on  currently  available
information. These statements are often, but not always, made through the use of
words or phrases such as `seek to',  `expects',  `should continue',  `believes',
`anticipates',   `estimates'   and  `intends'.   The  specific   forward-looking
statements cover, among other matters, the Company's internal review and related
restatement,  the reinsurance market, the Company's  operating results,  certain
financial  guidance such as the  corporate  tax rate,  the reduction of CRNA net
liabilities  ,  administration  expense ratio and  Corporate  Center costs,  the
rating  environment,  the prospect for improving results and expense reductions.
Such  statements  are  inherently  subject to certain  risks and  uncertainties.
Actual future results and trends could differ materially from those set forth in
such statements due to various  factors.  Such factors include the impact of our
ratings downgrade or a further lowering or loss of one of our financial strength
ratings; the impact of the restatement on our ratings and client  relationships;
uncertainties of assumptions used in our reserving process; risk associated with
implementing our business  strategies and our capital  improvement  measures and
the  run-off of our North  American  business;  cyclicality  of the  reinsurance
industry;  the  occurrence  of natural and man-made  catastrophic  events with a
frequency or severity  exceeding  our  estimates;  acts of terrorism and acts of
war;  changes in economic  conditions,  including  interest  and  currency  rate
conditions that could affect our investment  portfolio;  actions of competitors,
including  industry   consolidation  and  development  of  competing   financial
products;  a decrease in the level of demand for our  reinsurance  or  increased
competition  in our  industries  or  markets;  a loss  of our key  employees  or
executive  officers  without  suitable  replacements  being  recruited  within a
suitable  period of time;  our ability to address  material  weaknesses  we have
identified in our internal control environment; political risks in the countries
in which we operate or in which we reinsure  risks;  the  passage of  additional
legislation or the  promulgation of new regulation in a jurisdiction in which we
or our clients operate or where our subsidiaries are organized; the effect on us
and the insurance industry as a result of the  investigations  being carried out
by the US Securities and Exchange  Commission,  New York's Attorney  General and
other  governmental  authorities;  changes in our investment  results due to the
changed  composition of our invested assets or changes in our investment policy;
failure of our  retrocessional  reinsurers to honor their obligations or changes
in the  credit  worthiness  of our  reinsurers;  our  failure  to prevail in any
current or future arbitration or litigation;  and extraordinary events affecting
our  clients,  such as  bankruptcies  and  liquidations,  and  other  risks  and
uncertainties,  including  those  detailed in the Company's  filings with the US
Securities and Exchange Commission and the SWX Swiss Exchange.  The Company does
not assume any obligation to update any forward-looking statements, whether as a
result of new information, future events or otherwise.

www.converium.com

                                                                              11




                                                                              
Consolidated statements of income           Three months ended   Change       Year ended      Change
                                                December 31,                 December 31,
                                                         2004                        2004
In US$ million, unless noted                  2005    restated     (%)     2005    restated     (%)
------------------------------------------------------------------------------------------------------
Revenues
------------------------------------------------------------------------------------------------------
Gross premiums written                         375.4      434.5    -13.6  1,994.3    3,978.7    -49.9
------------------------------------------------------------------------------------------------------
Less ceded premiums written                    -60.9      -63.7     -4.4   -178.6     -252.6    -29.3
------------------------------------------------------------------------------------------------------
Net premiums written                           314.5      370.8    -15.2  1,815.7    3,726.1    -51.3
------------------------------------------------------------------------------------------------------
Net change in unearned premiums                127.0      313.8    -59.5    567.5      156.1   +263.5
------------------------------------------------------------------------------------------------------
Net premiums earned                            441.5      684.6    -35.5  2,383.2    3,882.2    -38.6
------------------------------------------------------------------------------------------------------
Net investment income                           78.0       84.6     -7.8    324.9      312.7     +3.9
------------------------------------------------------------------------------------------------------
Net realized capital gains (losses)             33.6        4.5      n.m.    25.5       46.5    -45.2
------------------------------------------------------------------------------------------------------
Other (loss) income                            -11.0        1.1      n.m.   -13.4       -8.2    +63.4
------------------------------------------------------------------------------------------------------
Total revenues                                 542.1      774.8    -30.0  2,720.2    4,233.2    -35.7
------------------------------------------------------------------------------------------------------

------------------------------------------------------------------------------------------------------
Losses, loss expenses and life benefits       -287.3     -491.6    -41.6 -1,775.9   -3,342.5    -46.9
------------------------------------------------------------------------------------------------------
Acquisition costs                             -147.2     -213.1    -30.9   -575.6     -912.4    -36.9
------------------------------------------------------------------------------------------------------
Other operating and administration expenses    -63.2      -59.3     +6.6   -210.8     -219.8     -4.1
------------------------------------------------------------------------------------------------------
Interest expense                                -8.0       -8.3     -3.6    -31.6      -33.1     -4.5
------------------------------------------------------------------------------------------------------
Impairment of goodwill                             -          -        -        -      -94.0      n.m.
------------------------------------------------------------------------------------------------------
Amortization of intangible assets               -0.2       -7.6      n.m.   -21.5       -9.9   +117.2
------------------------------------------------------------------------------------------------------
Restructuring costs                             +2.6        0.7      n.m.   -20.5       -2.7      n.m.
------------------------------------------------------------------------------------------------------
Total benefits, losses and expenses           -503.3     -779.2    -35.4 -2,635.9   -4,614.4    -42.9
------------------------------------------------------------------------------------------------------
Income (loss) before taxes                      38.8       -4.4      n.m.    84.3     -381.2      n.m.
------------------------------------------------------------------------------------------------------
Income tax expense                              -4.6       15.3      n.m.   -15.6     -201.3    -92.3
------------------------------------------------------------------------------------------------------
Net income (loss)                               34.2       10.9    213.8     68.7     -582.5   -111.8
------------------------------------------------------------------------------------------------------
Basic earnings (loss) per share (US$)           0.23       0.08      n.m.    0.47      -9.19      n.m.
------------------------------------------------------------------------------------------------------
Diluted earnings (loss) per share (US$)         0.23       0.08      n.m.    0.47      -9.19      n.m.
------------------------------------------------------------------------------------------------------



                                                                              12



Consolidated balance sheets                  Dec. 31,      Dec. 31,
                                                            2004
In US$ million, unless noted                  2005        restated
----------------------------------------------------------------------
Invested assets
----------------------------------------------------------------------
Held-to-maturity securities:
           Fixed maturities                      793.6          850.4
----------------------------------------------------------------------
Available-for-sale securities:
     Fixed maturities                          4,169.8        4,834.8
     Equity securities                           362.6          399.4
----------------------------------------------------------------------
Other investments                                253.1          279.2
----------------------------------------------------------------------
Short-term investments                            35.1          117.3
----------------------------------------------------------------------
Total investments                              5,614.2        6,481.1
----------------------------------------------------------------------
Funds Withheld Asset                           1,020.1        1,305.1
----------------------------------------------------------------------
Total invested assets                          6,634.3        7,786.2
----------------------------------------------------------------------
Other assets
----------------------------------------------------------------------
Cash and cash equivalents                        647.3          680.9
----------------------------------------------------------------------
Premiums receivables                           1,059.3        1,832.2
----------------------------------------------------------------------
Reserves for unearned premiums, retro             37.8           55.2
----------------------------------------------------------------------
Reinsurance assets:
     Underwriting reserves                       805.1          937.9
     Insurance and reinsurance balances
      receivable                                  37.6          139.3
----------------------------------------------------------------------
Funds held by reinsureds                       1,817.4        1,737.7
----------------------------------------------------------------------
Deposit assets                                   183.4          170.4
----------------------------------------------------------------------
Deferred policy acquisition costs                304.3          482.7
----------------------------------------------------------------------
Deferred income taxes                              1.0            6.2
----------------------------------------------------------------------
Other assets                                     298.4          358.6
----------------------------------------------------------------------
Total assets                                  11,825.9       14,187.3
----------------------------------------------------------------------
Liabilities
----------------------------------------------------------------------
Reinsurance liabilities:
----------------------------------------------------------------------
     Unpaid losses and loss expenses           7,568.9        8,908.3
----------------------------------------------------------------------
     Future life benefits, gross                 405.6          407.1
----------------------------------------------------------------------
     Insurance and reinsurance balances
      payable                                    226.3          583.5
----------------------------------------------------------------------
Reserves for unearned premium, gross             610.8        1,247.7
----------------------------------------------------------------------
Other reinsurance liabilities                    127.8           70.8
----------------------------------------------------------------------
Funds held under reinsurance contracts           332.9          194.8
----------------------------------------------------------------------
Deposit liabilities                              300.6          356.5
----------------------------------------------------------------------
Deferred income taxes                              8.1            8.2
----------------------------------------------------------------------
Accrued expenses and other liabilities           200.3          284.5
----------------------------------------------------------------------
Debt                                             391.2          391.1
----------------------------------------------------------------------
Total liabilities                             10,172.5       12.452.5
----------------------------------------------------------------------
Shareholders' equity
----------------------------------------------------------------------
Common stock                                     554.9          554.9
----------------------------------------------------------------------
Additional paid-in capital                     1,354.2        1,360.5
----------------------------------------------------------------------
Treasury stock                                    -1.5           -7.7
----------------------------------------------------------------------
Unearned stock compensation                       -3.5           -7.5
----------------------------------------------------------------------
Total accumulated other comprehensive
 income
     Accumulated other comprehensive income       -4.9           -7.7
----------------------------------------------------------------------
     Net unrealized gains on investments,
      net of taxes                                42.7          105.2
----------------------------------------------------------------------
     Cumulative translation adjustments           96.9          191.2
----------------------------------------------------------------------
Total accumulated other comprehensive
 income                                          134.7          288.7
----------------------------------------------------------------------
Retained deficit                                -385.4         -454.1
----------------------------------------------------------------------
Total shareholders' equity                     1,653.4        1,734.8
----------------------------------------------------------------------
Total liabilities and shareholders' equity    11,825.9       14,187.3
----------------------------------------------------------------------


                                                                              13




                                                                    

Segments                          Three months ended   Change       Year ended       Change
                                    December 31,                  December 31,

                                             2004                        2004
In US$ million, unless noted         2005  restated     (%)     2005   restated        (%)
--------------------------------     ----  --------    ------   -----  --------      -------
Standard Property & Casualty Reinsurance
---------------------------------------------------------------------------------------------
Gross premiums written               92.1     222.9     -58.7     803.1   1,509.1      -46.8
Net premiums written                 77.8     166.7     -53.3     739.0   1,377.5      -46.4
Net premiums earned                 161.4     268.1     -39.8     880.8   1,392.3      -36.7
Loss ratio(15)                       67.8%     81.2%  -13.4pts     82.8%     72.0%   +10.8pts
Acquisition costs ratio(16)          35.5%     35.8%   -0.3pts     20.6%     25.4%    -4.8pts
Administration expense ratio(17)     13.1%      7.4%   +5.7pts      6.1%      4.2%    +1.9pts
Combined ratio(18)                  116.4%    124.4%   -8.0pts    109.5%    101.6%    +7.9pts
Total investment result(19)          39.5      28.4     +39.1     122.0     113.9       +7.1
Segment income (loss)                24.0     -29.4       n.m.     46.7      91.5      -49.0
Retention ratio(20)                  84.5%     74.8%   -9.7pts     92.0%     91.3%    +0.7pts
---------------------------------------------------------------------------------------------

Specialty Lines
---------------------------------------------------------------------------------------------
Gross premiums written              239.5     516.8     -53.7     833.1   1,655.3      -49.7
Net premiums written                195.7     498.3     -60.7     737.7   1,565.3      -52.9
Net premiums earned                 215.3     410.8     -47.6   1,059.2   1,387.6      -23.7
Loss ratio(15)                       69.5%     84.3%  -14.8pts     72.9%     83.2%   -10.3pts
Acquisition costs ratio(16)          32.6%     30.4%   +2.2pts     24.9%     23.6%    +1.3pts
Administration expense ratio(17)      6.3%      3.6%   +2.7pts      7.6%      3.8%    +3.8pts
Combined ratio(18)                  108.4%    118.3%   -9.9pts    105.4%    110.6%    -5.2pts
Total investment result(19)          49.5      36.5     +35.6     142.9     147.5       -3.1
Segment income (loss)                32.6     -41.8       n.m.    109.5      -7.3        n.m.
Retention ratio (20)                 81.7%     96.4%  -14.7pts     88.5%     94.6%    -6.1pts
---------------------------------------------------------------------------------------------

Life & Health Reinsurance
---------------------------------------------------------------------------------------------
Gross premiums written               55.0      63.0     -12.7     318.8     327.9       -2.8
Net premiums written                 53.0      73.4     -27.8     306.4     313.2       -2.2
Net premiums earned                  71.6      94.3     -24.1     314.8     318.7       -1.2
Acquisitions costs ratio(16)         27.4%     26.5%   +0.9pts     29.3%     22.7%    +6.6pts
Administration expense ratio(17)      8.1%      5.2%   +2.9pts      5.3%      4.2%    +1.1pts
Total investment result(19)          11.2       5.2    +115.4      29.2      20.9      +39.7
Segment income                        6.6       5.8     +13.8      17.6      16.7       +5.4
Retention ratio(20)                  96.4%    116.5%  -20.1pts     96.1%     95.5%    +0.6pts
---------------------------------------------------------------------------------------------



-------------------------------------
(15) Loss ratio is defined as losses and loss adjustment expenses divided by net
     premiums earned.

(16) Acquisition  costs  ratio is defined as  acquisition  costs  divided by net
     premiums earned.

(17) Administration   expense   ratio  is   defined  as  other   operating   and
     administration   expenses  divided  by  net  premiums  written,   excluding
     Corporate Center segment expenses.

(18) Combined ratio is defined as non-life loss ratio (to premiums  earned) plus
     non-life  acquisition  costs  ratio  (to  premiums  earned)  plus  non-life
     administration expense ratio (to premiums written).

(19) Total  investment  result is  defined  as net  investment  income  plus net
     realized capital gains (losses).

(20) Retention  ratio  is  defined  as net  premiums  written  divided  by gross
     premiums written.

                                                                              14




                                                                     
Segments                        Three months ended   Change       Year ended       Change
                                    December 31,                  December 31,

                                             2004                          2004
In US$ million, unless noted      2005     restated    (%)      2005     restated    (%)
--------------------------------------------------------------------------------------------
Run-Off Segment
--------------------------------------------------------------------------------------------
Gross premiums written              -11.2    -368.2     -97.0      39.3     486.4     -91.9
--------------------------------------------------------------------------------------------
Net premiums written                -12.0    -367.6     -96.7      32.6     470.1     -93.1
--------------------------------------------------------------------------------------------
Net premiums earned                  -6.8     -88.6     -92.3     128.4     783.6     -83.6
--------------------------------------------------------------------------------------------
Total investment result(19)          11.4      19.0     -40.0      56.3      76.9     -26.8
--------------------------------------------------------------------------------------------
Segment income (loss)                15.0      87.8     -82.9      47.6    -296.0       n.m.
--------------------------------------------------------------------------------------------

Corporate Center
--------------------------------------------------------------------------------------------
Other operating and
 administration expenses            -22.8     -12.7      79.5     -50.1     -38.2     +31.2
--------------------------------------------------------------------------------------------



SIGNATURES

Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned, thereunto duly authorized.


                                               CONVERIUM HOLDING AG




                                               By:  /s/ Inga Beale
                                                    Name:      Inga Beale
                                                    Title:     CEO




                                               By:  /s/ Christian Felderer
                                                    Name: Christian Felderer
                                                    Title: General Legal Counsel



Date: March 17, 2006

                                                                              15