The Navigators Group, Inc. “Insuring a World in Motion”

1. The Navigators Group, Inc.“Insuring a World in Motion” Friedman Billings Ramsey 11th Annual Investor Conference November 30, 2004 New York City Stanley A. Galanski, President & Chief Executive Officer Paul J. Malvasio, Executive Vice President & Chief Financial Officer

2. This presentation may contain “forward-looking statements” as defined in the Private Securities Litigation Reform Act of 1995. Whenever used in this release, the words “estimate”, “expect”, “believe” or similar expressions are intended to identify such forward-looking statements. We cannot assure that results which we anticipate will be achieved, since results may differ materially because of known and unknown risks and uncertainties which we face. Please refer to Navigators’ most recent Forms 10-K and 10-Q and its other filings with the Securities and Exchange Commission for a description of Navigators’ business and the important factors which may affect that business. Navigators undertakes no obligation to publicly update or revise any forward- looking statement. 2

3. Navigators – Investment Highlights • A global leader in marine insurance • Business founded through Navigators Agencies in 1974 • Lloyd’s presence through Syndicate 1221 acquired in 1998 • Complements US operations and provides global market access • Commitment to underwriting profit • World-class specialty underwriting teams • Emphasis on bottom-line results, not market share • Diversifying opportunistically into attractive new business lines • Specialty Property & Casualty and Professional Liability • Excellent market opportunities and producer support • Portfolio diversification for stronger earnings stream across market cycles • Operating from a strong and leveragable platform • Rated “A” by A.M. Best and Standard and Poor’s • Lloyd’s licenses provide access to major world markets • No debt 3

4. Deep, Experienced Underwriting Team Senior Underwriting management team has an average of approximately 30 years in the industry and 14 years at Navigators. 4

5. Navigators’ Core Values • Underwriting Profit is the Primary Objective • Specializationin High Margin Businesses • Intellectual Capital – Hire and Build Top Notch Experts • Underwrite Severity but Utilize Reinsurance to Protect our Balance Sheet • Discipline – Don’t be Afraid to Shrink or Exit a Niche • Teamwork • Integrity, Professionalism and Pride 5

6. Growth and Portfolio Diversification Gross Premium Written by Segment ($’s in millions) Nine Months Year $607 $509 9% 22% 37% 32% $448 $456 10% 22% 37% 31% 5% 26% 29% 40% 8% 21% 38% 33% 6

7. Navigators Marine & Energy Lloyd’s Marine & Energy 30% of 2003 Year NWP 26% of Nine Months 2004 NWP • Largest and longest standing area of specialization for over 30 years • Navigators has an 80% participation in marine insurance pool operated by Navigators Agencies in 2004 and 2003 • Renewal rate increases averaged 4% in the nine months of 2004, 13% in 2003, and 21% in 2002 • Every regional office produced an underwriting profit in 2003 (excluding asbestos reserve strengthening) • 2004 nine month combined ratio of 90.9% (85.9% excluding Hurricane Ivan) 7

8. Marine & Energy – Mix of Business 2004 Nine Months Ended September 30, 2004 10% 15% 18% 8% 6% 6% 34% 3% 8

9. Marine & Energy – Rate Increases 9

10. 2003 U.S. Market Share ($ in thousands) Note: As reported by the AIMU. 10

11. Lloyd’s Marine & Energy Lloyd’s Marine & Energy 37% of 2003 Year NWP 40% of Nine Months 2004 NWP • Navigators Underwriting Agency, Ltd. manages Syndicate 1221 • Navigators provides 97.4% of Syndicate 1221’s gross capacity / $255mm for 2004 underwriting year compared to $200mm for 2003 • A Lloyd’s market leader in cargo and specie insurance • Millennium Consortium at Lloyd’s for construction/engineering risks • Expansion of Pennine operations positioned in three regional U.K. offices • Renewal rate decreases averaged 1.1% in nine months of 2004, compared to increases of 15% in year 2003 and 26% in year 2002 • 2004 nine month combined ratio of 93.8% (91.0% excluding Hurricane Ivan) 11

12. 2003 Lloyd’s Market Share (₤ in thousands) Source: Lloyd’s Market Association 12

13. Lloyd’s Marine Premium Rates % Base Year = 1992 13

14. Navigators Specialty Lloyd’s Marine & Energy 28% of 2003 Year NWP 26% of Nine Months 2004 NWP • Since 1995 has underwritten general liability insurance for small general and artisan contractors, mostly in California • Written on a non-admitted basis • Instituted a premium “cap” of $100 million GWP in 2003 • Achieved rate increases of 6.9% in the nine months of 2004 on top of 49% in 2003 and 30% in 2002, resulting in substantially reduced exposure and adequate pricing • Strategy to diversify by product line and geographically generated approximately 26% of 2004 Specialty GWP • Midwest branch operation since 2002 • Personal umbrella • Surety • Launched new product line, Umbrella Excess Liability, in November, 2004 • 2004 nine month combined ratio of 97.3% 14

15. Navigators Specialty Exposure Management Strategy – Dramatic Reduction in IFC In Force Policy Counts 15

16. Navigators Pro Lloyd’s Marine & Energy 5% of 2003 Year NWP 8% of Nine Months 2004 NWP • Introduced D&O liability insurance in late 2001 with team of experienced professionals • In late 2002, introduced lawyers professional liability and other miscellaneous professional liability coverages • Targeting small cap to mid cap public corporations and private companies • Claims made policies – reserves are substantially IBNR • As we have grown comfortable with the quality of underwriting, we have increased our net retention through a variable quota share • Established a London Branch presence in 2004; will expand to utilize Lloyd’s licenses in 2005 • 2004 nine month combined ratio of 79.1% 16

17. Navigators Pro - Premium Distribution 2004 GWP $52 Million $5.1 $1.8 $30.8 $14.3 17

18. Lloyd’s Marine & Energy Navigators Insurance CompanyHigh Quality Investment Portfolio At September 30, 2004 • Invested Assets: $840 million • Fixed Maturities and Cash: • 97.7% of portfolio • Average AA rating • Duration of approximately 3.7 years • Average yield of 3.5% for 3rd Quarter 2004 • Equity Securities: 2.3% of portfolio 14.6% 31.4% 2.3% 17.3% 14.9% 19.7% 18

19. Key Summary Financial Data Consolidated Group Data ($’s in millions) 19

20. Key Summary Financial Data Consolidated Group Data ($’s in thousands) *At December 31, 2003 20

21. Key Strategies: 2005 - 2007 • Maintain our Leadership Position in Marine • Maintain a Profitable Construction Segment • Complete the Build Out of Specialty Admitted Unit in Chicago • Expand Product Lines of Navigators Pro • Develop a Commercial Umbrella Book of Business • Expansion of European Branch Operations • Deploy Technologies to Reduce Costs and Enhance Results • Hire and Retain the Best and the Brightest 21

22. Why Navigators Now? • Global leader in marine insurance • Diversification strategy is on target • Experienced management team • Intellectual capital / specialty expertise • Commitment to underwriting profit • Proven track record • Operating from a strong and leveragable platform 22

23. Navigators“Insuring a World in Motion”