Slides from presentation by management

Investor Presentation

Quarter Ended March 31, 2012

Exhibit 99.1

This presentation may include forward-looking statements that reflect Alterra’s current views with respect to future events

and

financial

performance.

Statements

that

include

the

words

“expect,”

“intend,”

“plan,”

“believe,”

“project,”

“anticipate,”

“will,”

“may”

and similar statements of a future or forward-looking nature identify forward-looking statements. All forward-

looking statements address matters that involve risks and uncertainties. Accordingly, there are important factors that

could cause actual results to differ materially from those indicated in such statements and you should not place undue

reliance on any such statements.

These factors include, but are not limited to, the following: (1) the adequacy of loss and benefit reserves and the need to

adjust such reserves as claims develop over time; (2) the failure of any of the loss limitation methods employed; (3) the

effect of cyclical trends, including with respect to demand and pricing in the insurance and reinsurance markets; (4)

changes in general economic conditions, including changes in capital and credit markets; (5) any lowering or loss of

financial ratings; (6) the occurrence of natural or man-made catastrophic events with a frequency or severity exceeding

expectations; (7) actions by competitors, including consolidation; (8) the effects of emerging claims and coverage issues;

(9) the loss of business provided to Alterra by its major brokers; (10) the effect on Alterra’s investment portfolio of

changing financial market conditions, including inflation, interest rates, liquidity and other factors; (11) tax and regulatory

changes and conditions; (12) retention of key personnel; (13) the integration of new business ventures Alterra may enter

into; and (14) management’s response to any of the aforementioned factors.

The foregoing review of important factors should not be construed as exhaustive and should be read in conjunction with

the other cautionary statements that are included herein and elsewhere, including the Risk Factors included in Alterra’s

most recent reports on Form 10-K and Form 10-Q and other documents on file with the Securities and Exchange

Commission. Any forward-looking statements made in this presentation are qualified by these cautionary statements,

and there can be no assurance that the actual results or developments anticipated by Alterra will be realized or, even if

substantially realized, that they will have the expected consequences to, or effects on, Alterra or its business or

operations. Alterra undertakes no obligation to update publicly or revise any forward-looking statement, whether as a

result of new information, future developments or otherwise.

Cautionary Note Regarding Forward-Looking Statements

Alterra’s Franchise is Well Positioned For Success

Global underwriter of specialty insurance and reinsurance

Multiple

operating

platforms

Bermuda,

Ireland,

United

States, Lloyd's and Latin America

Strong franchise positions across multiple specialty

classes of business

Opportunistic and disciplined underwriting strategy

Strong culture of risk management

Analytical and quantitative underwriting orientation

Business mix shift towards shorter-tail lines

5 year average combined ratio (including cats) of 91.2%

Liquid balance sheet with conservative reserving track record

Shareholders’

equity ~ $2.8 billion at 3/31/12

Low operating and financial leverage

S&P rating and AM Best ratings of “A”

Proven track record of active capital management

Q1 2012 repurchases of $48.8 million and dividends of

$14.0

million,

2.2%

1/1/12

shareholders’

equity

2011 repurchases of $223.3 million and dividends of

$54.5

million,

9.5%

1/1/11

shareholders’

equity

Raised quarterly dividend by 17% in August 2011 to $0.14

per share

2011 GPW

Short-

Tail

Long-Tail

56%

44%

Insurance

43%

Reinsurance

57%

Alterra

Capital

Underwriting

Management

Framework

Cross-platform underwriting management

Board

Underwriting

Committee

provides

oversight

underwriting

strategy, processes and controls

Alterra Underwriting Council

manages and executes underwriting

portfolio strategy, processes and controls across all platforms

•

Metrics and portfolio management

•

Establish underwriting consistency and promulgate best practices

•

Comprised of all CUOs and selected underwriting thought leaders

Practice Groups

are established by the Underwriting Council to

address more specific and ongoing line of business

strategy/coordination issues

Underwriting Services

•

Facilitate underwriting

governance processes

•

Work with business

units to create/maintain

pricing models

•

Optimize capital

allocation

•

Facilitate resolution of

underwriting conflicts

•

Support Board

Underwriting

Committee

First Quarter 2012 Results

First quarter 2012 net operating diluted EPS

of $0.66 per share

P&C gross premiums written grew 5.3% to

$660.9 million

Driven by growth in all our segments

except our reinsurance segment

Net investment income of $58.7 million

compared to $57.8 million in 2011

Combined ratio of 92.6% compared to

112.5% in 2011

Diluted book value per share of $27.67 at

3/31/12 up from $26.91 at 12/31/11

Q1 2012 impacted by $9.2 million of income

from our investment in New Point IV.

Generated from equity earnings and fee

income.

P&C GPW

(5.3% increase)

112.5%

92.6%

Combined Ratio

Diluted Book Value per Share

(3.0% increase)

$26.91

$27.67

Dec 31, 2011

Mar 31, 2012

$627.4

$660.9

Mar 31, 2011

Mar 31, 2012

Growth in Book Value

Expansion into new lines and regions

2011 global industry cat losses were over $105 billion

Market stressed by historic low returns on invested assets

Cash flow levels deteriorating

Industry reserve redundancies diminishing

Property cat underwriting markets improving

Casualty lines showing flat to modest improvement

Pricing poised to positively move further with the next catalyst

Market Transitioning . . .

Alterra is positioned to be a beneficiary of improving market conditions

Pricing Is Improving For The First Time Since 1999. . .

But The Pace Remains Slow

More Rate Is Needed To Meaningfully Increase Exposure

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

Source: CIAB Pricing Survey

Large Accounts:

Rates Remain Below 1999

Medium Accounts:

Rates ~ 3% Above 1999

Small Accounts:

Rates ~ 12% Above 1999

2004

Insurance

Property

2003

Insurance

Excess Liability

Professional Liability

2005

Reinsurance

Property / Property Cat

Harbor Point formed

2006

Insurance

Aviation

2008

Lloyd's Insurance

Financial Institutions

Prof. Indemnity

Lloyd's Reinsurance

Accident / Health

Property

2007

U.S. E&S Insurance

Property

Inland Marine

U.S. Casualty

Reinsurance

Multi Peril Crop

Experienced &

highly quantitative

underwriting teams

Lead underwriters average over 20 years in the

business

High percentage of employees hold

professional designations

2009

Lloyd's

Casualty (non U.S.)

A&H Insurance

U.S. Specialty

Professional Liability

Latin America Reinsurance

2002

Traditional Re

Workers' Comp

Medical Malpractice

GL / PL

Aviation

Identifying & Recruiting "Franchise Players" Has Been

Instrumental In Our Success

2010

Alterra formed

by the merger of Max

Capital and Harbor Point

2011

Lloyd’s

Property Direct &

Facultative

U.S. Specialty

Excess Casualty

Local

Knowledge

Global

Reach

____________________

Note:

Pro forma gross premium written (“GPW”) represents the combined GPW of Max Capital and Harbor Point net of intercompany eliminations of GPW.

Global Insurance

(10.1% of Q1 2012 P&C GPW)

Reinsurance

(48.1% of Q1 2012 P&C GPW)

Professional

Liability

Property

Excess

Liability

Aviation

General Casualty

Property

Aviation

Workers Comp.

Professional Liability

Other

Med. Mal.

Marine & Energy

Agriculture

Q1 2012 GPW: $66.8 million

= pro forma

Alterra Has a Strong Market Position in Specialty Classes …

Credit/ Surety

Q1 2012 GPW: $318.4 million

19%

45%

38%

10%

36%

24%

U.S. Insurance

(15.8% of Q1 2012 P&C GPW)

Alterra at Lloyd’s

(22.1% of Q1 2012 P&C GPW)

…With an Attractive Position in the U.S. Market and Lloyd’s

Professional

Liability

Property

Marine

Excess/

General

Liability

Property

Agriculture

Aviation

Financial Institutions

Accident & Health

Q1 2012 GPW: $104.3 million

Q1 2012 GPW: $146.1 million

Int’l Casualty

Marine

Professional Liability

$194.3

$265.9

$324.0

$374.7

$104.3

$0.0

$100.0

$200.0

$300.0

$400.0

2008

2009

2010

2011

Q1 2012

$8.8

$129.0

$179.8

$253.1

$146.1

$0.0

$100.0

$200.0

$300.0

2008

2009

2010

2011

Q1 2012

12%

14%

33%

28%

33%

24%

11%

32%

Latin America

(3.8% of Q1 2012 P&C GPW)

…and Latin America

Property

Surety

Marine

General Liability

Q1 2012 GPW: $25.3 million

10%

65%

18%

$44.8

$91.8

$25.3

$0.0

$100.0

2010

2011

Q1 2012

North America

Europe

Other

Reinsurance

Insurance

(1)

2011 GPW = $1,904.1 million

____________________

(1)

Includes

Reinsurance

segment,

Life

Annuity

reinsurance

and

reinsurance

written

through

Lloyd’s

platform.

Diversified and Balanced Business Mix

Global Platform

2011

Line of Business

2011

Auto

Aviation

Marine & Energy

Agriculture

Accident & Health

Other Short

-Tail

Property

35%

Whole Account

General Casualty

17%

Financial

Institutions

Workers' Comp

Medical

Malpractice

Professional

Liability

20%

16%

10%

74%

57%

43%

____________________

Diversified Reinsurers

Property Focused Reinsurers

Diversified Platforms Generate More Consistent Margins

Alterra has performed well within its diversified peer group with less volatility than property focused reinsurers

Alterra has had one of

the lowest combined

ratios of its peer group

Median

173%

57%

62%

90%

66%

84%

126%

94%

Median

115%

85%

83%

96%

86%

94%

115%

96%

Alterra

109%

94%

96%

99%

94%

91%

103%

98%

72%

99%

47%

23%

81%

60%

48%

144%

108%

154%

102%

75%

92%

73%

60%

201%

25%

50%

75%

100%

125%

150%

175%

200%

225%

2005

2006

2007

2008

2009

2010

2011

Average

84%

96%

85%

76%

84%

75%

77%

97%

110%

145%

103%

97%

106%

99%

94%

124%

25%

50%

75%

100%

125%

150%

175%

200%

225%

2005

2006

2007

2008

2009

2010

2011

Average

Source: Company filings, SNL Financial.

Diversified reinsurers include RE, AXS, ACGL, TRH, PRE, AWH, ENH, AHL, PTP, AGII and ALTE . Property focused reinsurers include RNR, VR, MRH and FSR.

3 Year Return on Equity

Alterra’s ROEs Have Been Less Volatile Than Most Peers

____________________

Source:

JMP

Research,

SNL

Financial.

Three

years

ended

December

31,

2011.

Alterra ROE reflects Pro-Forma data for Max and Harbor Point prior to the merger in May 2010.

ACGL

AHL

AXS

AWH

MRH

PRE

PTP

RNR

ALTE

ENH

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

10%

12%

14%

16%

Std. Dev.

Our strategy is to diversify our book of business so that property cat

is one of many components of our business

Results demonstrate that we adequately manage our risk exposure

Our reserving process has been tested by large, recent loss events

including:

2011 Australia floods, New Zealand earthquake, Japan

earthquake and tsunami, US spring storms, Hurricane Irene, Thai

floods

2010 Chile earthquake, New Zealand earthquake

2008 Hurricanes Ike/Gustav

Superior Risk Management

Alterra’s losses from catastrophe events as a % of equity are

below our peer group average

Peer PML’s as a Percent of Shareholder’s Equity

____________________

Source: Dowling & Partners Research

Note: ALTE includes proportionate share of New Point Re IV. RNR and PRE do not disclose their PMLs for either 1-in-100 year events or 1-in-250 year events. All data

is based on RMS 11. RE and TRH utilize AIR.

10%

15%

20%

25%

30%

35%

FSR

ENH

ALTE

AXS

AHL

ACGL

AWH

MRH

TRH

PTP

As of December 31, 2011

1 in 100

1 in 250

2011 –

“The Year of The Cat”

Alterra’s Ratio Of Losses To Equity Are Below The Peer Group

__________________

Source: Company reports and SNL Financial

10%

15%

20%

25%

30%

35%

40%

45%

200

400

600

800

1,000

1,200

1,400

1,600

1,800

2,000

FSR

PRE

PTP

MRH

TRH

AHL

ENH

RNR

AGII

ACGL

AWH

ALTE

Losses

Percentage of January 1, 2011 Capital and Surplus

2010 –

Chile Earthquake / Windstorm Xynthia/

September New Zealand Earthquake

Alterra’s 2010 Losses Are Below Peer Group

____________________

10%

100

150

200

250

300

350

400

450

FSR

PTP (1)

VR (2)

RNR (3)

MRH

PRE

AHL

AXS (2)

TRH (2)

AWH

(2)(4)

ENH

AGII

(1)(5)

ACGL(1)

ALTE (6)

Ultimate Net Losses Reported

Percentage of January 1, 2010 Capital and Surplus

Source: Company filings and press releases; losses are generally disclosed net of tax and net of reinstatement premiums.

(1)

Q2 net losses reflect Q1 estimates plus reported development, if any.

(2)

Q2 net losses reflect only losses from the Chilean earthquake. Initial losses include the Chilean earthquake and Windstorm Xynthia.

(3)

Initial loss estimate reflects 50% to 90% of Reuters consensus net operating earnings prior to the earthquake, based on disclosure that net income would remain positive for the quarter.

(4)

Initial estimates based on Chile and Xynthia, ultimate losses include the Chilean, Haitian, and Baja earthquakes, Xynthia and the Australian hailstorms. Based on international catastrophe losses being two-thirds of total

catastrophe losses as disclosed in the earnings conference call.

(5)

Initial estimate is as of the first quarter conference call. Both initial and revised estimates reflect only the Chilean earthquake.

(6)

Pro forma; includes losses from Harbor Point and Max Capital prior to the merger. Expressed as a percentage of combined 12/31/09 equity prior to the special dividend.

2008 –

Hurricanes Ike / Gustav

____________________

Source: Company filings, as of 12/31/08. Losses are generally disclosed net of reinstatement premiums.

(1)

Equity includes preferred shares, which subsequently converted to common shares.

(2)

Results reflect Ike only.

(3)

Equity includes preferred shares, which subsequently converted to common shares.

(4)

TRH does not disclose specific losses but did lose "$169.7 million principally relating to Hurricane Ike."

10%

12%

14%

150

200

250

300

350

400

450

FSR

RNR

MRH

IPCR(1)

PTP(1)

ACGL

AXS

PRE(2)

HP(3)

AHL

ENH

ORH

TRH(4)

AWH

MXGL

Ultimate Net Losses Reported

Percentage of June 30, 2008 Capital and Surplus

100

PML goal of no more than 25% of starting capital in 1 in 250 year event

Adjust position as market pricing makes risk/reward attractive

Use RMS with “all switches on”

and gross-up factors on standard model

Incorporate AIR, market share, industry and client historical loss data

Capture detailed location data and put a premium on data quality

Historically our losses for events have been close to expected ranges

PML and aggregate usage is incorporated into our pricing models

Key In-force PMLs as of April 1, 2012

US wind

1 in 100 year event -

$496 million net loss (17.7% of 1/1/12 shareholders’

equity)

California earthquake

1 in 250 year event -

$358 million net loss (12.7% of 1/1/12 shareholders’

equity)

Europe wind

1 in 100 year event -

$144 million net loss (5.1% of 1/1/12 shareholders’

equity)

Cat Aggregate & PML Management

Reserve for Losses and Loss Expenses

Global Insurance

Reinsurance

U.S. Insurance

Alterra at Lloyd’s

Latin America

32%

33%

34%

36%

37%

35%

68%

67%

66%

64%

63%

65%

500

1,000

1,500

2,000

2,500

Q1 2012

Q4 2011

Q1 2012

Q4 2011

Q1 2012

Q4 2011

Q1 2012

Q4 2011

Q1 2012

Q4 2011

IBNR

Case

$1,296

$1,286

$ 382

$357

$483

$451

$46

$34

$2,115

$2,088

Favorable Reserve

Development

$5.9

$45.1

$90.8

$77.2

$105.5

$153.3

Development as a

% of Net Reserves

prior to

development

0.3%

2.5%

4.1%

3.4%

4.6%

Reserve Development History

($ in millions)

____________________

$1,840

$1,796

$2,128

$2,213

$2,985

$3,182

500

1,000

1,500

2,000

2,500

3,000

3,500

2006

2007

2008

2009

2010

2011

Net Loss Reserves

Note: Reserve development and net reserves prior to May 12, 2010 are for Max Capital only. Reserve development excludes changes in reserves resulting from changes in

premium estimates on prior years’ contracts.

High Quality, Liquid Investment Portfolio

As of March 31, 2012

Alterra maintains a high quality, liquid portfolio

95.7% of portfolio in fixed income/cash, which consists of highly

rated securities

Assets are generally matched to liabilities

Cycle

management

extends

investments

Cash balance $844.7 million or 10.8% of portfolio

Average fixed income duration of approximately 4.2 years, including

cash

60.0% of the cash and fixed maturities portfolio is held in cash,

government / agency-backed securities and “AAA”

securities

68.9% of fixed income portfolio rated “AA”

or better

Hedge fund investments are marked-to-market

Minimal exposure to selected asset classes

CMBS

$365.1

million

(5.5%

portfolio)

–

average

rating

AA+/Aa1

ABS of $264.5 million (4.0% of portfolio)

RMBS

$1,311.2

million

(19.8%

portfolio)

–

92.5%

agency-

backed

No CDO’s, CLO’s, SIV’s or other highly structured securities

Less than $13.3 million of OTTI losses over the last eight

quarters

Carrying Value $7.8 billion

March 31, 2012

Cash

11%

Other

Investments

Fixed Income

85%

European Government Holdings

Total European government holdings

represent $751.0 million, or 9.6%, of the

$7.8 billion investment portfolio.

No exposure to Greece, Portugal, Italy,

Ireland or Spain

European financial institutions

Total European financial institution

holdings represent $421.5 million, or

5.4%, of the $7.8 billion investment

portfolio.

Two largest holdings, which total $121.3

million, are with government-backed

financial institutions.

European Exposure

As of March 31, 2012

France

37%

Germany

33%

Netherlands

20%

Belgium

United

Kingdom

Denmark

Other

European

Investment

Bank

16%

KFW

13%

Credit Suisse

Lloyds

UBS

BNP Paribas

HSBC

Barclays

Other

34%

____________________

Note:

Primary price / diluted book value multiple as of 5/9/12.

Well Positioned to Build Shareholder Value

Franchise positions in attractive specialty markets

Established operating platforms provide global access to business

Diversified business portfolio across casualty and property lines

Opportunistic

approach

–

nimble

and

responsive

market

trends

High-quality, liquid investment portfolio

Invested asset leverage intended to drive more consistent returns

Balance sheet strength with low leverage / financial flexibility

Attractive entry point –

price / diluted book value of 0.88x

Expands our market clout and

footprint

Reduces underwriting risk

Increases fee income

Earlier recognition of profits

Assists

the

risk

management

process

Can dial down as market

pricing improves

Reduces Volatility and

Improves the Near-term ROE

Disciplined Underwriting Management

Benefits of Ceding Premium Include:

GPW $ millions

Q1 2012

Q1 2011

Period over Period

Growth %

Bermuda/ Dublin

130.5

97.2

US Reinsurance

24.4

26.2

GPW on contracts bound by Alterra in the period

154.9

123.4

25.5%

Alterra’s share of New Point Re IV premiums

27.9

Total property reinsurance gross premiums

182.8

123.4

48.1%

Total property reinsurance net premiums

122.0

90.3

35.1%

Growth in Property Reinsurance Premiums

Excluding premium adjustments and reinstatement premiums.

34.8% share of New Point Re IV gross premiums written. These premiums are not included in Alterra’s reported gross premiums

written as the investment in New Point Re IV is accounted for under the equity method.

Appendices

March 31,

December 31,

2012

2011

Cash & Fixed Maturities

7,472

7,528

Other Investments

333

287

Premium Receivables

870

715

Losses Recoverable

1,108

1,068

Other Assets

793

588

Total Assets

10,576

10,186

Property & Casualty Losses

4,323

4,217

Life & Annuity Benefits

1,204

1,191

Deposit Liabilities

151

Funds Withheld

112

Unearned Premium

1,222

1,021

Senior Notes

441

Other Liabilities

291

244

Total Liabilites

7,725

7,377

Shareholders' Equity

2,851

2,809

10,576

10,186

Strong Balance Sheet

($ in millions)

YTD Results Comparison

($ in millions)

Quarter ended

Mar. 31,

2012

2011

Gross Premiums Written

661

628

Net Premiums Earned

338

380

Net Investment Income

Net Realized and Unrealized Gains (Losses) on Investments

(19)

Other Than Temporary Impairment Charges

(5)

(1)

Other Income

Total Revenues

422

419

Total Losses, Expenses & Taxes

343

466

Net Income (Loss)

(47)

Net Operating Income (Loss)

(25)

Property & Casualty Underwriting

Loss Ratio

61.0%

80.2%

Expense Ratio

31.6%

32.3%

Combined Ratio

92.6%

112.5%

Quarter ended March 31, 2012

($ in millions)

Totals in table may not add due to rounding. (1) Property and Casualty only.

Diversified Operating Platform

Property & Casualty

Global

Insurance

U.S.

Insurance

Reinsurance

Alterra at

Lloyd's

Latin

America

Total

Life & Annuity

Reinsurance

Corporate

Consolidated

Gross premiums written

$66.8

$104.3

$318.4

$146.1

$25.3

$660.9

$0.4

661.3

Reinsurance premiums ceded

(43.3)

(70.5)

(59.5)

(38.6)

(12.6)

(224.4)

(224.5)

Net premiums written

$23.5

$33.8

$258.9

$107.6

$12.7

$436.5

$0.4

436.9

Earned premiums

$94.1

$96.2

$194.7

$72.9

$19.5

$477.4

$0.4

477.8

Earned premiums ceded

(47.1)

(40.5)

(26.8)

(20.0)

(5.3)

(139.7)

Net premiums earned

47.0

55.8

167.9

52.9

14.2

337.8

0.4

338.2

Net losses and loss expenses

(18.1)

(37.6)

(101.2)

(38.7)

(10.5)

(206.0)

Claims and policy benefits

(13.5)

Acquisition costs

(0.1)

(7.7)

(38.7)

(9.4)

(3.8)

(59.6)

(0.1)

(59.7)

General and administrative expenses

(6.5)

(12.3)

(17.1)

(9.1)

(2.3)

(47.1)

(47.2)

Other income

0.8

0.1

4.4

5.3

Underwriting income (loss)

23.2

(1.7)

15.4

(4.4)

(2.3)

30.3

n/a

Net investment income

14.8

43.9

58.7

25.5

(5.4)

Corporate other income

Interest expense

(8.6)

Net foreign exchange gains

Corporate general and administrative expenses

(12.9)

Income before taxes

$1.6

$42.6

$74.4

Loss ratio

38.5%

67.3%

60.3%

73.2%

74.0%

61.0%

Acquisition cost ratio

0.1%

13.8%

23.0%

17.9%

26.4%

17.6%

General and administrative expense ratio

13.8%

22.0%

10.2%

17.2%

15.9%

14.0%

Combined ratio

(1)

52.4%

103.1%

93.4%

108.2%

116.2%

92.6%

Net realized and unrealized gains on

investments

Net impairment losses recognized in

earnings