Exhibit 99.1

Contact:                 Lily Outerbridge

Investor Relations

(441) 298-0760

PLATINUM UNDERWRITERS HOLDINGS, LTD.  REPORTS RECORD FINANCIAL RESULTS FOR THE SECOND QUARTER ENDED JUNE 30, 2009

HAMILTON, BERMUDA, July 21, 2009 – Platinum Underwriters Holdings, Ltd. (NYSE: PTP) today reported net income of $98.1 million, which is a record $1.90 per diluted common share, for the quarter ended June 30, 2009.

The results for the quarter include net premiums earned of $232.5 million, a decrease of 9.9% from the same quarter last year, and net favorable development of $23.6 million, as compared with net favorable development of $36.8 million for the same quarter last year.

Michael D. Price, Platinum’s Chief Executive Officer, commented, “Our record net income per diluted common share reflects disciplined underwriting, net favorable reserve development, lower than expected catastrophe activity, good investment results and active capital management.  Our book value per share was $39.23 as of June 30, 2009, an increase of 9.7% from March 31, 2009 and 13.4% from December 31, 2008.”

Mr. Price added, “So far this year, we have found more attractive underwriting conditions for property and marine than for casualty.  However, we may be approaching the bottom of the casualty reinsurance market.”

Results for the quarter ended June 30, 2009 are summarized as follows:

·Net income was $98.1 million, or $1.90 per diluted common share.

·Net premiums written were $208.1 million and net premiums earned were $232.5 million.

·GAAP combined ratio was 76.9%.

·Net investment income was $44.1 million.

·Net realized gains on investments were $10.8 million.

Results for the quarter ended June 30, 2009 as compared with the quarter ended June 30, 2008 are summarized as follows:

·Net income decreased $4.2 million (or 4.1%).

·Net premiums written decreased $16.7 million (or 7.4%) and net premiums earned decreased $25.5 million (or 9.9%).

·GAAP combined ratio increased 8.5 percentage points.

·Net investment income decreased $2.9 million (or 6.1%).

·Net realized gains on investments were $10.8 million for the quarter ended June 30, 2009 compared with net realized losses on investments of $6.2 million for the quarter ended June 30, 2008.

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Net premiums written for Platinum’s Property and Marine, Casualty and Finite Risk segments for the quarter ended June 30, 2009 were $113.4 million, $87.4 million and $7.3 million, respectively, representing 54.5%, 42.0% and 3.5%, respectively, of the total net premiums written. Combined ratios for these segments were 66.5%, 88.4% and 118.4%, respectively, for the quarter ended June 30, 2009. Compared with the quarter ended June 30, 2008, net premiums written decreased by $5.2 million (or 4.4%) and $15.4 million (or 15.0%) in the Property and Marine and Casualty segments, respectively, and increased $3.9 million in the Finite Risk segment.

Results for the six months ended June 30, 2009 are summarized as follows:

·Net income was $183.1 million, or $3.47 per diluted common share.

·Net premiums written were $453.4 million and net premiums earned were $480.2 million.

·GAAP combined ratio was 78.5%.

·Net investment income was $78.3 million.

·Net realized gains on investments were $31.4 million.

 

Results for the six months ended June 30, 2009 as compared with the six months ended June 30, 2008 are summarized as follows:

·Net income decreased $24.5 million (or 11.8%).

·Net premiums written decreased $67.7 million (or 13.0%) and net premiums earned decreased $79.6 million (or 14.2%).

·GAAP combined ratio increased 4.8 percentage points.

·Net investment income decreased $17.7 million (or 18.4%).

·Net realized gains on investments were $31.4 million for the six months ended June 30, 2009 compared with net realized losses on investments of $3.2 million for the six months ended June 30, 2008

Net premiums written for Platinum’s Property and Marine, Casualty and Finite Risk segments for the six months ended June 30, 2009 were $255.1 million, $185.5 million, and $12.8 million, respectively, representing 56.3%, 40.9% and 2.8%, respectively, of the total net premiums written.  Combined ratios for these segments were 71.9%, 85.4% and 113.6%, respectively, for the six months ended June 30, 2009.  Compared with the six months ended June 30, 2008, net premiums written decreased $32.3 million (or 11.2%) and $43.0 million (or 18.8%) in the Property and Marine and Casualty segments, respectively, and increased $7.5 million in Finite Risk segment.

Total assets were $4.97 billion as of June 30, 2009, an increase of $41.0 million (or 0.8%) from $4.93 billion as of December 31, 2008.  Cash, cash equivalents and fixed maturity investments were $4.40 billion as of June 30, 2009, an increase of $139.3 million (or 3.3%) from $4.26 billion as of December 31, 2008.

Shareholders’ equity was $1.95 billion as of June 30, 2009, an increase of $143.3 million (or 7.9%) from $1.81 billion as of December 31, 2008.  Book value per common share was $39.23 as of June 30, 2009 based on 49.8 million common shares outstanding, an increase of $4.65 (or 13.4%) from $34.58 as of December 31, 2008 based on 47.5 million common shares outstanding.  Book value reflects common share repurchases of $41.3 million at a weighted average cost, including commissions, of $27.84 per share during the quarter ended June 30, 2009.

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Financial Supplement

Platinum has posted a financial supplement on the Financial Reports page of the Investor Relations section of its website (Financial Supplement).  The financial supplement provides additional detail regarding the financial performance of Platinum and its business segments.

Teleconference

Platinum will host a teleconference to discuss its financial results on Wednesday, July 22, 2009 at 8:00 a.m. Eastern time.  The call may be accessed by dialing 888-637-7705 (US callers) or 913-312-1298 (international callers), or in a listen-only mode via the Investor Relations section of Platinum’s website at www.platinumre.com.  Those who intend to participate in the teleconference should register at least ten minutes in advance to ensure access to the call.

The teleconference will be recorded and a replay will be available from 11:00 a.m. Eastern time on Wednesday, July 22, 2009 until midnight Eastern time on Wednesday, July 29, 2009.  To access the replay by telephone, dial 888-203-1112 (US callers) or 719-457-0820 (international callers) and specify passcode 1518494. The teleconference will also be archived on the Investor Relations section of Platinum’s website at www.platinumre.com for the same period of time.

Non-GAAP Financial Measures

In presenting the Company's results, management has included and discussed certain schedules containing financial measures that are not calculated under standards or rules that comprise accounting principles generally accepted in the United States (GAAP). Such measures, including segment underwriting income (or loss) related underwriting ratios and fully converted book value per common share, are referred to as non-GAAP. These non-GAAP measures may be defined or calculated differently by other companies. Management believes these measures, which are used to monitor the results of operations, assist in understanding the Company. These measures should not be viewed as a substitute for those determined in accordance with GAAP. Reconciliations of such measures to the most comparable GAAP figures such as income before income tax expense or benefit and total shareholders’ equity is presented in the attached financial information in accordance with Regulation G.

About Platinum

Platinum Underwriters Holdings, Ltd. (NYSE: PTP) is a leading provider of property, casualty and finite risk reinsurance coverages, through reinsurance intermediaries, to a diverse clientele on a worldwide basis.  Platinum operates through its principal subsidiaries in Bermuda and the United States.  The Company has a financial strength rating of A (Excellent) from A.M. Best Company, Inc.  For further information, please visit Platinum’s website at www.platinumre.com.

Safe Harbor Statement Regarding Forward-Looking Statements:

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934 (the “Exchange Act”).  Forward-looking statements are based on our current plans or expectations that are inherently subject to significant business, economic and competitive uncertainties and contingencies.  These uncertainties and contingencies can affect actual results and could cause actual results to differ materially from those expressed in any forward-looking statements made by, or on behalf of, us.  In particular, statements using words such as “may,” “should,” “estimate,” “expect,” “anticipate,” “intend,” “believe,” “predict,” “potential,” or words of similar import generally involve forward-looking statements.  The inclusion of forward-looking statements in this press release should not be considered as a representation by us or any other person that our current plans or expectations will be achieved.  Numerous factors could cause our actual results to differ materially from those in forward-looking statements, including, but not limited to, severe catastrophic events over which we have no control, the effectiveness of our loss limitation methods and pricing models, the adequacy of our liability for unpaid losses and loss adjustment expenses, our ability to maintain our A.M. Best Company, Inc. rating, the cyclicality of the property and casualty reinsurance business, conducting operations in a competitive environment, our ability to maintain our business relationships with reinsurance brokers, the availability of retrocessional reinsurance on acceptable terms, market volatility and interest rate and currency exchange rate fluctuation, tax, regulatory or legal restrictions or limitations applicable to us or the property and casualty reinsurance business generally, general political and economic conditions, including the effects of civil unrest, acts of terrorism, war or a prolonged United States or global economic downturn or recession; and changes in our plans, strategies, objectives, expectations or intentions, which may happen at any time at our discretion. As a consequence, our future financial condition and results may differ from those expressed in any forward-looking statements made by or on behalf of us.  The foregoing factors should not be construed as exhaustive.  Additionally, forward-looking statements speak only as of the date they are made, and we undertake no obligation to revise or update forward-looking statements to reflect new information or circumstances after the date hereof or to reflect the occurrence of future events.

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Platinum Underwriters Holdings, Ltd.

Condensed Consolidated Balance Sheets

As of June 30, 2009 and December 31, 2008

(amounts in thousands, except per share amounts)

	June 30, 2009		December 31, 2008
	(Unaudited)
Assets
Investments	$	4,049,472	$	3,371,886
Cash, cash equivalents and short-term investments		349,786		888,053
Reinsurance premiums receivable		261,817		307,539
Accrued investment income		33,813		29,041
Reinsurance balances (prepaid and recoverable)		24,715		23,310
Deferred acquisition costs		43,720		50,719
Funds held by ceding companies		120,232		136,278
Other assets		84,583		120,337
Total assets	$	4,968,138	$	4,927,163
Liabilities
Unpaid losses and loss adjustment expenses	$	2,394,330	$	2,463,506
Unearned premiums		190,757		218,890
Debt obligations		250,000		250,000
Commissions payable		121,780		125,551
Other liabilities		58,567		59,819
Total liabilities		3,015,434		3,117,766
Total shareholders' equity		1,952,704		1,809,397
Total liabilities and shareholders' equity	$	4,968,138	$	4,927,163
Book value per common share  (a)	$	39.23	$	34.58

(a) Book value per common share is determined by dividing shareholders' equity, excluding capital attributable to preferred shares, by actual common shares outstanding.

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Platinum Underwriters Holdings, Ltd.

Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited)

For the Three and Six Months Ended June 30, 2009 and 2008

(amounts in thousands, except per share amounts)

	Three Months Ended						Six Months Ended
	June 30, 2009			June 30, 2008			June 30, 2009		June 30, 2008
Revenue
Net premiums earned	$	232,462			257,982			480,214	$	559,833
Net investment income		44,077			46,932			78,323		95,994
Net realized gains (losses) on investments		10,794			(6,168	)		31,364		(3,196	)
Other income		5,212			716			5,444		620
Total revenue		292,545			299,462			595,345		653,251
Expenses
Net losses and LAE		124,945			93,392			269,109		253,595
Net acquisition expenses		38,338			66,137			78,494		126,679
Net change in fair value of derivatives		106			959			2,523		1,769
Net impairment losses		3,256			-			6,664		-
Operating expenses		22,906			25,100			43,774		46,790
Net foreign currency exchange (gains) losses		(537	)		1,998			459		(2,871	)
Interest expense		4,756			4,751			9,511		9,501
Total expenses		193,770			192,337			410,534		435,463
Income before income tax expense		98,775			107,125			184,811		217,788
Income tax expense		645			4,768			1,759		10,260
Net income		98,130			102,357			183,052		207,528
Preferred dividends		-			2,602			1,301		5,204
Net income attributable to common shareholders	$	98,130			99,755			181,751	$	202,324
Basic
Weighted average common shares outstanding		50,580			48,468			50,105		50,286
Basic earnings per common share	$	1.94			2.06			3.63	$	4.02
Diluted
Adjusted weighted average common shares outstanding		51,594			56,097			52,744		58,021
Diluted earnings per common share	$	1.90			1.82			3.47	$	3.58
Comprehensive income
Net income	$	98,130			102,357			183,052	$	207,528
Other comprehensive (income) loss, net of deferred taxes		64,958			(38,876	)		63,382		(42,997	)
Comprehensive income	$	163,088			63,481			246,434	$	164,531

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Platinum Underwriters Holdings, Ltd.

Segment Reporting

For the Three Months Ended June 30, 2009 and 2008

($ in thousands)

Three Months Ended June 30, 2009 (Unaudited)
Segment underwriting results	Property and Marine			Casualty			Finite Risk			Total
Net premiums written	$	113,405			87,459			7,253		$	208,117
Net premiums earned		128,316			99,161			4,985			232,462
Net losses and LAE		62,807			61,042			1,096			124,945
Net acquisition expenses		13,526			20,406			4,406			38,338
Other underwriting expenses		9,123			6,130			400			15,653
Total underwriting expenses		85,456			87,578			5,902			178,936
Segment underwriting income (loss)	$	42,860			11,583			(917	)		53,526
Net investment income											44,077
Net realized gains on investments											10,794
Net impairment losses											(3,256	)
Net change in fair value of derivatives											(106	)
Net foreign currency exchange gains											537
Other income											5,212
Corporate expenses not allocated to segments											(7,253	)
Interest expense											(4,756	)
Income before income tax expense										$	98,775
GAAP underwriting ratios:
Loss and LAE		48.9	%		61.6	%		22.0	%		53.7	%
Acquisition expense		10.5	%		20.6	%		88.4	%		16.5	%
Other underwriting expense		7.1	%		6.2	%		8.0	%		6.7	%
Combined		66.5	%		88.4	%		118.4	%		76.9	%
Three Months Ended June 30, 2008
Segment underwriting results
Net premiums written	$	118,588			102,893			3,379		$	224,860
Net premiums earned		141,716			113,245			3,021			257,982
Net losses and LAE		33,367			66,783			(6,758	)		93,392
Net acquisition expenses		24,774			32,214			9,149			66,137
Other underwriting expenses		9,635			6,991			365			16,991
Total underwriting expenses		67,776			105,988			2,756			176,520
Segment underwriting income	$	73,940			7,257			265			81,462
Net investment income											46,932
Net realized losses on investments											(6,168	)
Net impairment losses											-
Net change in fair value of derivatives											(959	)
Net foreign currency exchange losses											(1,998	)
Other income											716
Corporate expenses not allocated to segments											(8,109	)
Interest expense											(4,751	)
Income before income tax expense										$	107,125
GAAP underwriting ratios:
Loss and LAE		23.5	%		59.0	%		(223.7	%)		36.2	%
Acquisition expense		17.5	%		28.4	%		302.8	%		25.6	%
Other underwriting expense		6.8	%		6.2	%		12.1	%		6.6	%
Combined		47.8	%		93.6	%		91.2	%		68.4	%
The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.

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Platinum Underwriters Holdings, Ltd.

Segment Reporting

For the Six Months Ended June 30, 2009 and 2008

($ in thousands)

Six Months Ended June 30, 2009 (Unaudited)
Segment underwriting results	Property and Marine			Casualty			Finite Risk			Total
Net premiums written	$	255,140			185,473			12,776		$	453,389
Net premiums earned		261,987			209,121			9,106			480,214
Net losses and LAE		140,258			120,183			8,668			269,109
Net acquisition expenses		30,890			46,627			977			78,494
Other underwriting expenses		17,282			11,799			700			29,781
Total underwriting expenses		188,430			178,609			10,345			377,384
Segment underwriting income (loss)	$	73,557			30,512			(1,239	)		102,830
Net investment income											78,323
Net realized gains on investments											31,364
Net impairment losses											(6,664	)
Net change in fair value of derivatives											(2,523	)
Net foreign currency exchange losses											(459	)
Other income											5,444
Corporate expenses not allocated to segments											(13,993	)
Interest expense											(9,511	)
Income before income tax expense										$	184,811
GAAP underwriting ratios:
Loss and LAE		53.5	%		57.5	%		95.2	%		56.0	%
Acquisition expense		11.8	%		22.3	%		10.7	%		16.3	%
Other underwriting expense		6.6	%		5.6	%		7.7	%		6.2	%
Combined		71.9	%		85.4	%		113.6	%		78.5	%
Six Months Ended June 30, 2008
Segment underwriting results
Net premiums written	$	287,405			228,469			5,257		$	521,131
Net premiums earned		295,106			260,740			3,987			559,833
Net losses and LAE		95,406			166,176			(7,987	)		253,595
Net acquisition expenses		45,428			69,702			11,549			126,679
Other underwriting expenses		18,231			13,786			675			32,692
Total underwriting expenses		159,065			249,664			4,237			412,966
Segment underwriting income (loss)	$	136,041			11,076			(250	)		146,867
Net investment income											95,994
Net realized losses on investments											(3,196	)
Net impairment losses											-
Net change in fair value of derivatives											(1,769	)
Net foreign currency exchange gains											2,871
Other income											620
Corporate expenses not allocated to segments											(14,098	)
Interest expense											(9,501	)
Income before income tax expense										$	217,788
GAAP underwriting ratios:
Loss and LAE		32.3	%		63.7	%		(200.3	%)		45.3	%
Acquisition expense		15.4	%		26.7	%		289.7	%		22.6	%
Other underwriting expense		6.2	%		5.3	%		16.9	%		5.8	%
Combined		53.9	%		95.7	%		106.3	%		73.7	%
The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.

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