Allied World Reports 44% Increase in Second Quarter 2009 Net Income; 13.4% Increase in Total Book Value Year To Date

PEMBROKE, Bermuda -

Allied World Assurance Company Holdings, Ltd (NYSE: AWH) today reported net income of US$113.7 million, or US$2.22 per diluted share, for the second quarter of 2009 compared to net income of US$79.2 million, or US$1.56 per diluted share, for the second quarter of 2008. Net income for the six months ended June 30, 2009 was US$245.1 million, or US$4.79 per diluted share, compared to net income of US$210.2 million, or US$4.12 per diluted share, for the first six months of 2008.

The company reported operating income of US$112.8 million, or US$2.20 per diluted share, for the second quarter of 2009 compared to operating income of US$83.2 million, or US$1.64 per diluted share, for the second quarter of 2008. Operating income for the six months ended June 30, 2009 was US$250.4 million, or US$4.89 per diluted share, compared to operating income of US$211.2 million, or US$4.14 per diluted share, for the first six months of 2008.

President and Chief Executive Officer Scott Carmilani commented, “Allied World continues to deliver significant book value growth to our shareholders. The company’s annualized operating return on equity is 20% for the first half of the year and our total book value has grown more than 13% since year end 2008. The company’s total capital now exceeds US$3.2 billion, which positions us very well as our initiatives to expand the breadth of our global insurance and reinsurance operations have begun to take hold.”

Mr. Carmilani continued, “Shareholders expect consistently strong results and we are proud that we have continued to deliver them. Our results are a testament to our underwriting culture and sound investment strategies that have been a hallmark of Allied World since our inception in 2001. These strengths continue to serve us well as we navigate through the current industry cycle and focus on product lines and geographic markets where we believe opportunities exist.”

Underwriting Results

Gross premiums written were US$492.8 million in the second quarter of 2009, a 10.3% increase compared to US$446.8 million in the second quarter of 2008. For the six months ended June 30, 2009, gross premiums written totaled US$972.4 million, a 15.3% increase compared to US$843.7 million in the first six months of 2008. Net premiums written were US$361.4 million in the second quarter of 2009, a 12.9% increase compared to US$320.3 million in the second quarter of 2008. For the six months ended June 30, 2009, net premiums written totaled US$766.5 million, an 18.5% increase compared to US$646.8 million in the first six months of 2008. These increases were primarily due to the inclusion of the Darwin Professional Underwriters, Inc. (”Darwin”) business and increased writings by our other U.S. offices, offset by reductions in our international and reinsurance segments that were largely due to the non-renewal of business that did not meet our underwriting requirements.

Net premiums earned in the second quarter of 2009 were US$333.7 million, a 24.1% increase compared to US$268.9 million in the second quarter of 2008. For the six months ended June 30, 2009, net premiums earned totaled US$657.6 million, a 21.3% increase from net premiums earned of US$541.9 million in the first six months of 2008. These increases were primarily due to the inclusion of the Darwin business.

The combined ratio was 83.1% in the second quarter of 2009 compared to 93.2% in the second quarter of 2008. The loss and loss expense ratio was 53.3% in the second quarter of 2009 compared to 66.2% in the second quarter of 2008. During the second quarter of 2009, the company recorded net favorable reserve development on prior loss years of US$36.6 million, a benefit of 11.0 percentage points to the company’s loss and loss expense ratio for the quarter. This compares to the second quarter of 2008, where the company recorded net favorable reserve development on prior loss years of US$39.8 million, a benefit of 14.8 percentage points to the company’s loss and loss expense ratio for that quarter. Absent prior year reserve adjustments, the loss and loss expense ratio related to the second quarter of 2009 was 64.3% compared to 81.0% for the second quarter of 2008. During the three months ended June 30, 2008, we experienced higher than expected loss activity, which included net losses and loss expenses incurred from the floods in the U.S. Midwest and a gas pipeline explosion in Australia.

For the six months ended June 30, 2009, the combined ratio was 79.3% compared to 85.6% in the first six months of 2008. For the first six months of 2009, the company recorded net favorable reserve development on prior loss years of US$96.8 million, a benefit of 14.7 percentage points to the company’s loss and loss expense ratio. For the first six months of 2008, the company recorded net favorable reserve development on prior loss years of US$92.9 million, a benefit of 17.1 percentage points to the company’s loss and loss expense ratio.

The company’s expense ratio was 29.8% for the second quarter of 2009 compared to 27.0% for the second quarter of 2008. The expense ratio was 29.7% for the six months ended June 30, 2009 compared to 26.3% in the first six months of 2008. As part of our ongoing strategic initiatives, the company has significantly expanded its existing U.S. operations. Our overall staff count increased to 614 as of June 30, 2009 from 335 as of June 30, 2008, primarily driven by the additional staff of Darwin. As a result of the increased staff count, salary and employee welfare costs increased by US$14.5 million and US$28.3 million during the three and six months ended June 30, 2009, respectively, compared to the same periods in 2008.

Investment Results

Net investment income in the second quarter of 2009 was US$76.5 million, an increase of 5.8% from the US$72.3 million of net investment income in the second quarter of 2008. For the six months ended June 30, 2009, net investment income was US$154.4 million, an increase of 3.4% over the US$149.3 million of net investment income in the first six months of 2008. These increases were primarily the result of growth in the fixed-maturity portfolio as of June 30, 2009 compared to June 30, 2008, partially offset by slightly lower yields on our fixed-maturity portfolio. The company recorded net realized investment gains of US$5.1 million and US$41.7 million for the three and six months ended June 30, 2009. Consistent with the adoption of the Financial Accounting Standard Board Staff Position 115-2 and 124-2 “Recognition and Presentation of Other-Than-Temporary Impairments” (”FSP FAS 115-2″) on April 1, 2009, the company recorded US$5.5 million of credit impairment losses on investments in the second quarter of 2009. Prior to April 1, 2009, the company recorded realized losses on any securities that had a market value below amortized cost and for which our investment managers held discretion to sell the security. During the six months ended June 30, 2009, the company recorded total net impairment charges recognized in earnings of US$47.4 million.

As of June 30, 2009 and December 31, 2008, net accumulated unrealized gains were US$48.7 million and US$105.6 million, respectively. The change in net unrealized investment gains from December 31, 2008 to June 30, 2009 resulted from the cumulative effect adjustment related to the adoption of FSP FAS 115-2 of US$136.8 million, partially offset by unrealized gains in our fixed-maturity portfolio of US$79.9 million generally due to tightening of credit spreads on corporate bonds and mortgage-backed securities.

Shareholders’ Equity

As of June 30, 2009, our shareholders’ equity was US$2.7 billion, a 13.4% increase compared to US$2.4 billion as of December 31, 2008. The increase was primarily the result of net income of US$245.1 million and net unrealized gains on investments of US$79.9 million recognized during the six months ended June 30, 2009.

The company’s annualized net income return on average shareholders’ equity for the three and six months ended June 30, 2009 was 17.7% and 19.6%, respectively. The company’s annualized operating return on average shareholders’ equity for the three and six months ended June 30, 2009 was 17.6% and 20.0%, respectively.

As of June 30, 2009, diluted book value per share was US$51.78, an increase of 12.4% compared to US$46.05 as of December 31, 2008.

Quarterly Dividend

Allied World announced today that its Board of Directors has declared a quarterly dividend of US$0.18 per common share. The dividend will be payable on September 10, 2009 to shareholders of record on August 25, 2009.

Investment Supplement

Allied World will be providing additional information on its investment portfolio as of June 30, 2009. This information will be available at the “Investor Relations” section of the company’s website at www.awac.com.

Financial Supplement

A financial supplement relating to the second quarter of 2009 will be available at the “Investor Relations” section of the company’s website at www.awac.com.

Conference Call

Allied World will host a conference call on Friday, August 7, 2009 at 8:30 a.m. (Eastern Time) to discuss the second quarter 2009 financial results. The public may access a live webcast of the conference call at the “Investor Relations” section of the company’s website at www.awac.com. In addition, the conference call can be accessed by dialing +1-866-713-8563 (U.S. and Canada callers) or +1-617-597-5311 (international callers) and entering the passcode 90724924 approximately ten minutes prior to the call.

Following the conclusion of the presentation, a replay of the call will be available through Friday, August 21, 2009 by dialing +1-888-286-8010 (U.S. and Canada callers) or +1-617-801-6888 (international callers) and entering the passcode 76678076. In addition, the webcast will remain available online through Friday, August 21, 2009 at www.awac.com.

Non-GAAP Financial Measures

In presenting the company’s results, management has included and discussed in this press release certain non generally accepted accounting principles (”non-GAAP”) financial measures within the meaning of Regulation G as promulgated by the U.S. Securities and Exchange Commission. Management believes that these non-GAAP measures, which may be defined differently by other companies, better explain the company’s results of operations in a manner that allows for a more complete understanding of the underlying trends in the company’s business. However, these measures should not be viewed as a substitute for those determined in accordance with generally accepted accounting principles (”GAAP”).

“Operating income” is an internal performance measure used by the company in the management of its operations and represents after-tax operational results excluding, as applicable, net realized investment gains or losses, net impairment charges recognized in earnings and foreign exchange gain or loss. The company excludes net realized investment gains or losses, net impairment charges recognized in earnings and net foreign exchange gain or loss from its calculation of operating income because the amount of these gains or losses is heavily influenced by, and fluctuates in part according to, the availability of market opportunities. The company believes these amounts are largely independent of its business and underwriting process and including them may distort the analysis of trends in its insurance and reinsurance operations. In addition to presenting net income determined in accordance with GAAP, the company believes that showing operating income enables investors, analysts, rating agencies and other users of its financial information to more easily analyze the company’s results of operations in a manner similar to how management analyzes the company’s underlying business performance. Operating income should not be viewed as a substitute for GAAP net income.

The company has included “diluted book value per share” because it takes into account the effect of dilutive securities; therefore, the company believes it is a better measure of calculating shareholder returns than book value per share.

“Annualized net income return on average shareholders’ equity” (”ROAE”) is calculated using average shareholders’ equity, excluding the average after tax unrealized gains or losses on investments. Unrealized gains (losses) on investments are primarily the result of interest rate and risk premium movements and the resultant impact on fixed income securities. Such gains (losses) are not related to management actions or operational performance, nor are they likely to be realized. Therefore, the company believes that excluding these unrealized gains (losses) provides a more consistent and useful measurement of operating performance, which supplements GAAP information. In calculating ROAE, the net income (loss) available to shareholders for the period is multiplied by the number of such periods in a calendar year in order to arrive at annualized net income (loss) available to shareholders. The company presents ROAE as a measure that is commonly recognized as a standard of performance by investors, analysts, rating agencies and other users of its financial information.

“Annualized operating return on average shareholders’ equity” is calculated using operating income (as defined above and annualized in the manner described for net income (loss) available to shareholders under ROAE above), and average shareholders’ equity, excluding the average after tax unrealized gains (losses) on investments. Unrealized gains (losses) are excluded from equity for the reasons outlined in the annualized net income return on average shareholders’ equity explanation above.

Reconciliations of these financial measures to their most directly comparable GAAP measures are included in the attached tables.

About Allied World Assurance Company

Allied World Assurance Company Holdings, Ltd, through its subsidiaries, is a global provider of innovative property, casualty and specialty insurance and reinsurance solutions, offering superior client service through offices in Bermuda, the United States, Europe and Hong Kong. Our insurance and reinsurance subsidiaries are rated A (Excellent) by A.M. Best Company. For further information on Allied World, please visit our website at www.awac.com.

Cautionary Statement Regarding Forward-Looking Statements

Any forward-looking statements made in this press release reflect our current views with respect to future events and financial performance and are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Such statements involve risks and uncertainties, which may cause actual results to differ materially from those set forth in these statements. For example, our forward-looking statements could be affected by the ability to recognize the benefits of the Darwin acquisition; pricing and policy term trends; increased competition; the impact of acts of terrorism and acts of war; greater frequency or severity of unpredictable catastrophic events; investigations of market practices and related settlement terms; negative rating agency actions; the adequacy of our loss reserves; the company or its subsidiaries becoming subject to significant income taxes in the United States or elsewhere; changes in regulations or tax laws; changes in the availability, cost or quality of reinsurance or retrocessional coverage; adverse general economic conditions including those related to the ongoing financial crisis; and judicial, legislative, political and other governmental developments, as well as management’s response to these factors, and other factors identified in our filings with the U.S. Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date on which they are made. We are under no obligation (and expressly disclaim any such obligation) to update or revise any forward-looking statement that may be made from time to time, whether as a result of new information, future developments or otherwise.

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Expressed in thousands of United States dollars, except share and per share amounts) Quarter Ended Six Months Ended June 30, June 30, 2009 2008 2009 2008 Revenues: Gross premiums written $492,782 $446,784 $972,379 $843,657 Premiums ceded (131,344) (126,534) (205,903) (196,835) Net premiums written 361,438 320,250 766,476 646,822 Change in unearned premiums (27,770) (51,374) (108,836) (104,874) Net premiums earned 333,668 268,876 657,640 541,948 Net investment income 76,537 72,345 154,391 149,276 Net realized investment gains 5,093 21,514 41,695 36,349 Net impairment charges recognized in earnings (5,474) (25,907) (47,437) (37,277) Other income 369 - 835 - Total revenue 410,193 336,828 807,124 690,296 Expenses: Net losses and loss expenses 177,719 178,084 326,216 321,581 Acquisition costs 36,963 26,265 74,091 53,105 General and administrative expenses 62,560 46,380 120,990 89,651 Interest expense 9,522 9,513 19,969 19,023 Foreign exchange (gain)/loss (1,222) (399) (387) 77 Total expenses 285,542 259,843 540,879 483,437 Income before income taxes 124,651 76,985 266,245 206,859 Income tax expense/(recovery) 10,981 (2,220) 21,167 (3,291) NET INCOME $113,670 $79,205 $245,078 $210,150 PER SHARE DATA: Basic earnings per share $2.30 $1.62 $4.96 $4.33 Diluted earnings per share $2.22 $1.56 $4.79 $4.12 Weighted average common shares outstanding 49,523,459 48,897,931 49,386,549 48,585,015 Weighted average common shares and common share equivalents outstanding 51,257,887 50,873,712 51,215,808 51,013,633 Dividends declared per share $0.18 $0.18 $0.36 $0.36

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (Expressed in thousands of United States dollars, except share and per share amounts) As of As of June 30, December 31, ASSETS: 2009 2008 Fixed maturity investments available for sale, at fair value (amortized cost: 2009: $6,223,018; 2008: $5,872,031) $6,286,561 $6,032,029 Fixed maturity investments trading, at fair value 233,583 - Other invested assets trading, at fair value 132,694 69,902 Other invested assets available for sale, at fair value (cost: 2009: $4; 2008: $89,229) 4 55,199 Total investments 6,652,842 6,157,130 Cash and cash equivalents 475,668 655,828 Restricted cash 59,074 50,439 Securities lending collateral - 171,026 Insurance balances receivable 421,773 347,941 Prepaid reinsurance 220,113 192,582 Reinsurance recoverable 909,716 888,314 Accrued investment income 56,651 50,671 Deferred acquisition costs 153,428 135,780 Goodwill 268,532 268,532 Intangible assets 69,280 71,410 Balances receivable on sale of investments 266,610 12,371 Net deferred tax assets 31,676 22,452 Other assets 45,191 47,603 Total assets $9,630,554 $9,072,079 LIABILITIES: Reserve for losses and loss expenses $4,713,727 $4,576,828 Unearned premiums 1,066,726 930,358 Unearned ceding commissions 56,825 49,599 Reinsurance balances payable 132,948 95,129 Securities lending payable - 177,010 Balances due on purchase of investments 359,216 - Syndicated loan - 243,750 Senior notes 498,857 498,796 Accounts payable and accrued liabilities 60,828 83,747 Total liabilities $6,889,127 $6,655,217 SHAREHOLDERS’ EQUITY: Common shares, par value $0.03 per share: issued and outstanding 2009: 49,524,492; 2008: 49,036,159 shares $1,486 $1,471 Additional paid-in capital 1,332,200 1,314,785 Retained earnings 1,359,072 994,974 Accumulated other comprehensive income, net of tax 48,669 105,632 Total shareholders’ equity $2,741,427 $2,416,862 Total liabilities and shareholders’ equity $9,630,554 $9,072,079

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD UNAUDITED CONSOLIDATED SEGMENT DATA (Expressed in thousands of United States dollars, except for ratio information) U.S. International Quarter Ended June 30, 2009 Insurance Insurance Reinsurance Total Gross premiums written $182,712 $191,985 $118,085 $492,782 Net premiums written 127,469 116,170 117,799 361,438 Net premiums earned 111,025 111,807 110,836 333,668 Other income 369 - - 369 Net losses and loss expenses (46,842) (74,101) (56,776) (177,719) Acquisition costs (13,543) (1,667) (21,753) (36,963) General and administrative expenses (31,061) (19,914) (11,585) (62,560) Underwriting income 19,948 16,125 20,722 56,795 Net investment income 76,537 Net realized investment gains 5,093 Net impairment charges recognized in earnings (5,474) Interest expense (9,522) Foreign exchange gain 1,222 Income before income taxes $124,651 GAAP Ratios: Loss and loss expense ratio 42.2% 66.3% 51.2% 53.3% Acquisition cost ratio 12.2% 1.5% 19.6% 11.1% General and administrative expense ratio 28.0% 17.8% 10.5% 18.7% Combined ratio 82.4% 85.6% 81.3% 83.1% U.S. International Quarter Ended June 30, 2008 Insurance Insurance Reinsurance Total Gross premiums written $65,664 $244,521 $136,599 $446,784 Net premiums written 35,644 147,980 136,626 320,250 Net premiums earned 31,681 118,087 119,108 268,876 Net losses and loss expenses (22,980) (81,377) (73,727) (178,084) Acquisition costs (2,632) 379 (24,012) (26,265) General and administrative expenses (14,275) (20,974) (11,131) (46,380) Underwriting (loss) income (8,206) 16,115 10,238 18,147 Net investment income 72,345 Net realized investment gains 21,514 Net impairment charges recognized in earnings (25,907) Interest expense (9,513) Foreign exchange gain 399 Income before income taxes $76,985 GAAP Ratios: Loss and loss expense ratio 72.5% 68.9% 61.9% 66.2% Acquisition cost ratio 8.3% (0.3%) 20.2% 9.8% General and administrative expense ratio 45.1% 17.8% 9.3% 17.2% Combined ratio 125.9% 86.4% 91.4% 93.2%

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD UNAUDITED CONSOLIDATED SEGMENT DATA (Expressed in thousands of United States dollars, except for ratio information) U.S. International Six Months Ended June 30, 2009 Insurance Insurance Reinsurance Total Gross premiums written $336,081 $317,904 $318,394 $972,379 Net premiums written 243,313 205,127 318,036 766,476 Net premiums earned 216,292 223,001 218,347 657,640 Other income 835 - - 835 Net losses and loss expenses (101,019) (113,294) (111,903) (326,216) Acquisition costs (27,954) (2,727) (43,410) (74,091) General and administrative expenses (59,525) (38,733) (22,732) (120,990) Underwriting income 28,629 68,247 40,302 137,178 Net investment income 154,391 Net realized investment gains 41,695 Net impairment charges recognized in earnings (47,437) Interest expense (19,969) Foreign exchange gain 387 Income before income taxes $266,245 GAAP Ratios: Loss and loss expense ratio 46.7% 50.8% 51.3% 49.6% Acquisition cost ratio 12.9% 1.2% 19.9% 11.3% General and administrative expense ratio 27.5% 17.4% 10.4% 18.4% Combined ratio 87.1% 69.4% 81.6% 79.3% U.S. International Six Months Ended June 30, 2008 Insurance Insurance Reinsurance Total Gross premiums written $101,486 $415,821 $326,350 $843,657 Net premiums written 58,763 262,093 325,966 646,822 Net premiums earned 61,724 240,739 239,485 541,948 Net losses and loss expenses (39,063) (153,156) (129,362) (321,581) Acquisition costs (5,617) (455) (47,033) (53,105) General and administrative expenses (28,843) (40,608) (20,200) (89,651) Underwriting (loss) income (11,799) 46,520 42,890 77,611 Net investment income 149,276 Net realized investment gains 36,349 Net impairment charges recognized in earnings (37,277) Interest expense (19,023) Foreign exchange loss (77) Income before income taxes $206,859 GAAP Ratios: Loss and loss expense ratio 63.3% 63.6% 54.0% 59.3% Acquisition cost ratio 9.1% 0.2% 19.6% 9.8% General and administrative expense ratio 46.7% 16.9% 8.4% 16.5% Combined ratio 119.1% 80.7% 82.0% 85.6%

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD UNAUDITED OPERATING INCOME RECONCILIATION (Expressed in thousands of United States dollars, except share and per share amounts) Quarter Ended Six Months Ended June 30, June 30, 2009 2008 2009 2008 Net income $113,670 $79,205 $245,078 $210,150 Net realized investment gains (5,093) (21,514) (41,695) (36,349) Net impairment charges recognized in earnings 5,474 25,907 47,437 37,277 Foreign exchange (gain)/loss (1,222) (399) (387) 77 Operating income $112,829 $83,199 $250,433 $211,155 Weighted average common shares outstanding: Basic 49,523,459 48,897,931 49,386,549 48,585,015 Diluted 51,257,887 50,873,712 51,215,808 51,013,633 Basic per share data: Net income $2.30 $1.62 $4.96 $4.33 Net realized investment gains (0.10) (0.44) (0.84) (0.75) Net impairment charges recognized in earnings 0.11 0.53 0.96 0.77 Foreign exchange (gain)/loss (0.03) (0.01) (0.01) - Operating income $2.28 $1.70 $5.07 $4.35 Diluted per share data Net income $2.22 $1.56 $4.79 $4.12 Net realized investment gains (0.10) (0.42) (0.81) (0.71) Net impairment charges recognized in earnings 0.11 0.51 0.92 0.73 Foreign exchange (gain)/loss (0.03) (0.01) (0.01) - Operating income $2.20 $1.64 $4.89 $4.14

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD UNAUDITED DILUTED BOOK VALUE PER SHARE RECONCILIATION (Expressed in thousands of United States dollars, except share and per share amounts) As of As of As of June 30, December 31, June 30, 2009 2008 2008 Price per share at period end $40.83 $40.60 $39.62 Total shareholders’ equity 2,741,427 2,416,862 2,378,046 Basic common shares outstanding 49,524,492 49,036,159 48,977,635 Add: unvested restricted share units 947,180 971,907 892,995 Add: Performance based equity awards 1,329,661 1,345,903 1,345,903 Add: dilutive options/warrants outstanding 6,569,616 6,371,151 6,896,842 Weighted average exercise price per share 33.70 33.38 30.85 Deduct: options bought back via treasury method (5,423,031) (5,237,965) (5,371,066) Common shares and common share equivalents outstanding 52,947,918 52,487,155 52,742,309 Basic book value per common share $55.35 $49.29 $48.55 Diluted book value per common share $51.78 $46.05 $45.09

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD UNAUDITED ANNUALIZED RETURN ON SHAREHOLDERS’ EQUITY RECONCILIATION (Expressed in thousands of United States dollars, except for percentage information) Quarter Ended Six Months Ended June 30, June 30, 2009 2008 2009 2008 Opening shareholders’ equity $2,491,860 $2,394,620 $2,416,862 $2,239,842 Deduct: accumulated other comprehensive income (48,204) (135,626) (105,632) (136,214) Adjusted opening shareholders’ equity 2,443,656 2,258,994 2,311,230 2,103,628 - - Closing shareholders’ equity $2,741,427 $2,378,046 $2,741,427 $2,378,046 Deduct: accumulated other comprehensive income (48,669) (39,048) (48,669) (39,048) Adjusted closing shareholders’ equity 2,692,758 2,338,998 2,692,758 2,338,998 Average shareholders’ equity $2,568,207 $2,298,996 $2,501,994 $2,221,313 Net income available to shareholders $113,670 $79,205 $245,078 $210,150 Annualized net income available to shareholders 454,680 316,820 490,156 420,300 Annualized return on average shareholders’ equity - net income available to shareholders 17.7% 13.8% 19.6% 18.9% Operating income available to shareholders $112,829 $83,199 $250,433 $211,155 Annualized operating income available to shareholders 451,316 332,796 500,866 422,310 Annualized return on average shareholders’ equity - operating income available to shareholders 17.6% 14.5% 20.0% 19.0%

Source: Allied World Assurance Company Holdings, Ltd

Media, Faye Cook, Vice President, Marketing & Communications, +1-646-794-0453, faye.cook at awac.com, or Investors, Keith J. Lennox, Investor Relations Officer, +1-646-794-0750, keith.lennox at awac.com, both of Allied World