Slide 1: Q3 2026 Investor Presentation
1 Q3 2026 Investor Presentation
Slide 2: Forward Looking Statements
2 Forward Looking Statements Statements in this press release that are not historical facts are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, and are intended to be covered b
Slide 3: NB Bancorp, Inc. Overview
NB Bancorp, Inc. Overview N3 Banco:
Slide 4: Overview of NB Bancorp, Inc.
4 Overview of NB Bancorp, Inc. Total Assets $7.7B Total Gross Loans $6.8B Total Deposits $6.5B Total Equity $857M TCE/ TA 10.82%² Tier 1 Leverage Ratio 11.25%¹ Tier 1 Capital Ratio 11.64%¹ Total Capital Ratio 12.42%¹ Q3’26 Operating ROAA 1.26%² Q3’26 Operating ROATCE 11.05%² Q3’26 NIM 3.97% Q3’26 Op
Slide 5: Performance Post-IPO
5 Performance Post-IPO 1) See Appendix for reconciliation of non-GAAP financial metrics 5 Asset Growth in $M +49.0% Deposits in $M +50.5% YTD Operating EPS1 +484.6% Net Interest Margin +14.1% Operating ROAA1 +46.4% Share Price +12.1% $5,158 $7,684 IPO Q3'26 $4,333 $6,521 IPO Q3'26 $0.26 $1.52 IPO Q3
Slide 6: Branch network and deposit market share
6 Our branch network covers the metro-west area of Boston, southern New Hampshire and surrounding communities which are our primary deposit market areas. We consider our primary lending market area to be the Greater Boston metropolitan area and surrounding communities in Massachusetts, eastern Conne
Slide 7: Strength of Growing Deposit Base
7 Strength of Growing Deposit Base Over the two-year period ended June 30, 2026 (latest market data available), each Needham Bank branch experienced growth that matched or exceeded growth in its respective market. In aggregate, Needham Bank achieved growth at over 9 times the overall market growth d
Slide 8: Industry Drivers of Local Market
8 Largest Employers Boston MSA 2026-2031 Projected HHI Δ Massachusetts 2025 GDP by Industry Boston MSA Median HHI ($) Industry Drivers of Local Market 1) Other industries include accommodation and food services, waste management and remediation services, educational services, management of companies
Slide 9: Branches Opened - 2026
9 Allston May 2026 Salem, NH June 2026 Prudential Center – Boston August 2026 Opened Branches - 2026
Slide 10: Experienced Institutional Leadership
10 Experienced Institutional Leadership Joseph Campanelli Chairman, President & CEO William Darcey President & CEO – Provider Insurance Group Paul J. Ayoub Chair – Nutter McClennen & Fish LLP Susan Elliott Retired EVP – Federal Home Loan Bank of Boston Angela Jackson CEO – Future Forward Strategies
Slide 11: Investment Highlights
11 Investment Highlights 11 Experienced management team and talent base to grow market share, invest for the future and serve the community Focused on driving franchise value via relationship-based banking and active community involvement History of consistent earnings through various market cycles
Slide 12: Financial Highlights for the Third Quarter 2026
12 Financial Highlights for the Third Quarter 2026 • GAAP Net income of $23.1 million, or $0.58 per diluted share for the quarter. • Operating Net Income1 (Non-GAAP) of $23.8 million, or $0.59 per diluted share for the quarter. • Gross loans increased $343.8 million, or 5.3%, to $6.78 billion, from
Slide 13: Financial Highlights for the Third Quarter 2026 (Cont.)
13 Financial Highlights for the Third Quarter 2026 (Cont.) • Allowance for Credit Losses (“ACL”) decreased $3.8 million, or 4.6%, during the quarter, primarily driven by the previously mentioned PCD charge off and reduced need for specific reserves on individually evaluated loans, partially offset b
Slide 14: Financial Overview
14 Financial Overview
Slide 15: Targeted Balance Sheet Growth
15 Total Deposits ($M) Tangible Common Equity ($M) Total Assets ($M) Total Gross Loans ($M) Targeted Balance Sheet Growth 15 $2,923 $3,592 $4,533 $5,158 $7,001 $7,226 $7,447 $7,684 2021 2022 2023 2024 2025 Q1'26 Q2'26 Q3'26 $2,105 $3,015 $3,889 $4,333 $5,986 $6,210 $6,423 $6,766 2021 2022 2023 2024
Slide 16: Track Record of Strong Performance
16 Operating Return on Avg. Tangible Common Equity (%)1 Operating Net Income ($M)1, 2 Operating Return on Average Assets (%)¹ Operating Return on Average Equity (%)¹ Track Record of Strong Performance 1) See Appendix for reconciliation of non-GAAP financial metrics 2) Q1, Q2 and Q3 ’26 operating net
Slide 17: Track Record of Strong Performance (Cont.)
17 Operating Noninterest Income / Average Assets (%)¹ Operating Noninterest Expense / Average Assets (%)¹ Net Interest Margin (%) Operating Efficiency Ratio (%)¹ Track Record of Strong Performance (Cont.) 1) See Appendix for reconciliation of non-GAAP financial metrics 17 2.81% 3.49% 3.41% 3.53% 3.7
Slide 18: Capital Ratios
18 11.28%¹ 17.41%² 13.59%² 13.00%² 12.76%² 12.42%² 2021 2022 2023 2024 2025 Q1'26 Q2'26 Q3'26 10.54%¹ 16.51%² 12.83%² 12.19%² 11.95%² 11.64%² 2021 2022 2023 2024 2025 Q1'26 Q2'26 Q3'26 Tier 1 Capital Ratio (%) Total Capital Ratio (%) Tangible Common Equity / Tangible Assets (%) Leverage Ratio (%) Ca
Slide 19: Loan Portfolio & Asset Quality
19 Loan Portfolio & Asset Quality
Slide 20: Diversified Loan Portfolio
20 Commercial Real Estate 34.01% 1-4 Family including HELOCs 21.10% Commercial & Industrial 16.78% Construction & Development 12.49% Multifamily 8.63% Warehouse 3.51% Consumer 3.48% Note: Loan composition reflects regulatory holding company data Diversified Loan Portfolio Q3’26 Yield on Loans: 6.66%
Slide 21: Loan Portfolio Stats – September 30, 2026
21 Loan balances above are not shown net of deferred fees Loan Portfolio Stats – September 30, 2026 Loan Type Balance Wtd. Avg. Rate Wtd. Avg. Maturity (Yrs) Fixed Rate (%) Variable Rate (%) Commercial Real Estate $2,304,739 6.38% 9.1 18.0% 82.0% 1-4 Family (incl. HELOCs) $1,429,780 5.36% 26.0 41.9%
Slide 22: Mortgage Warehouse Portfolio Overview
22 Mortgage Warehouse Portfolio Overview • Our $238.1 million mortgage warehouse lending portfolio, acquired from BankProv, consists of facility lines to non-bank mortgage origination companies (“originators”). o It is a national platform with relationships across the United States that offers Maste
Slide 23: Enterprise Value (EV) Portfolio
23 Enterprise Value (“EV”) Portfolio • Our C&I portfolio as of September 30, 2026, includes a $95.9 million EV portfolio, acquired from BankProv. The EV portfolio consists of loans and lines to entities collateralized by the cash flows and underlying enterprise value of the borrowing entity. • This
Slide 24: Overview of EV Portfolio
24 Service 53% Trade Contractors 21% Manufacturing 12% Healthcare 13% Retail / Wholesale 1% EV By Type Overview of EV Portfolio $95.9M Q3’26 Total 24 EV Balance Trend 2025 - Q4 187,691 2026 - Q1 159,115 2026 - Q2 129,627 2026 - Q3 95,865 90,000 110,000 130,000 150,000 170,000 190,000 210,000 2025 -
Slide 25: Loan Portfolio Concentrations
25 Construction & Development / Total Indicative Risk-Based Capital (%)¹ Commercial Real Estate / Total Indicative Risk-Based Capital (%)¹ Loan Portfolio Concentrations 1) Financials reflect regulatory holding company data 25 280% 277% 342% 187% 202% 294% 318% 314% 344% 2020 2021 2022 2023 2024 2025
Slide 26: Commercial Real Estate Portfolio
26 Multi-Family, 27% Office, 15% Hospitality 14% Mixed Use 11% Industrial, 8% Retail, 9% Other, 15% Cannabis Facility, 25% Retail Industrial, 26% 17% Special Purpose 11% Office 6% Other, 15% Owner-Occupied CRE By Collateral Type Non-Owner-Occupied CRE By Collateral Type Commercial Real Estate Portfo
Slide 27: Office Portfolio Overview
27 Non-Owner-Occupied - Office 69% Non-Owner-Occupied - Medical Office 14% Owner-Occupied - Office 8% Other 9% 1) Includes commercial real estate and construction office loans Office Portfolio Overview¹ Our $388.1 million office portfolio consists principally of suburban Class A and B office space u
Slide 28: Overview of C&I Portfolio
28 Chicago, IL 15% Boston 8% Newport Beach, CA 8% New York, NY 6% Other 63% Structured Finance 26% Middle Market 17% Renewable Energy 16% Cannabis 14% Cannabis Bridge Financing 11% Bridge Financing 6% Small Business / Other 11% C&I By Type C&I By Geography Overview of C&I Portfolio $1.14B Q3’26 Tota
Slide 29: Overview of Construction Lending
29 Boston, MA 19% Weston, MA 8% Milton, MA 7% Salem, NH 5% Needham, MA 5% Cambridge, MA 5% Other 50% Condos 27% Land 16% Multi-Family 12% Single Family 10% Hotel/Motel 7% Other 28% Construction By Type Construction By Geography Overview of Construction Lending $846M Q3’26 Total $846M Q3’26 Total 29
Slide 30: Consumer Loans Overview
30 Consumer Loans Overview • Amounts above exclude purchased premiums or discounts 30 Loan Type Q3 2025 Q4 2025 Q1 2026 Q2 2026 Q3 2026 Purchased: Solar $ 45,678 $ 44,410 $ 43,080 $ 41,150 $ 39,398 Loans Held for Sale - Boat Loans - 63,447 63,971 59,927 55,906 Boat Loans 42,487 238 - - - Home Improv
Slide 31: Consumer Loans Trends
31 Consumer Loans Trends 31 $0 $500 $1,000 $1,500 $2,000 $2,500 $3,000 $- $20,000 $40,000 $60,000 $80,000 $100,000 $120,000 $140,000 $160,000 $180,000 Q3 2025 Q4 2025 Q1 2026 Q2 2026 Q3 2026 Balance (thousands) Period Overview of Purchased Consumer Loans Net Charge Offs - Purchased (3ME) Net Charge
Slide 32: Cannabis Business Highlights
32 Cannabis Business Highlights • As of September 30, 2026, we had outstanding loan balances of $576.3 million to cannabis businesses: • $401.3 million was direct to cannabis entities; • $175.0 million was indirect to cannabis entities; • Weighted average LTV and DSCR was 46.8% and 3.22, respectivel
Slide 33: Asset Quality
33 $6.0 $13.0 $10.8 $13.9 $7.5 $15.3 $13.2 $12.8 $35.9 $30.3 $14.5 $23.3 $4.5 $8.3 $0.0 2021 2022 2023 2024 2025 Q1'26 Q2'26 Q3'26 NBBK Nonaccruals ($M) BankProv Nonaccruals ($M) TDRs ($M) OREO ($M) 0.87% 0.83% 0.83% 0.89% 1.46% 1.29% 1.28% 1.16% 175% 117% 298% 280% 201% 176% 297% 217% 0.0% 100.0% 2
Slide 34: Historically Strong Credit Culture
34 1) Reflects annualized metrics • Note: Values may not sum due to rounding Historically Strong Credit Culture NCOs / Average Loans (%)¹ • Our loan portfolio consists primarily of commercial real estate and multifamily loans, one-to four-family residential real estate loans, construction and land d
Slide 35: Funding & Liquidity Management
35 Funding & Liquidity Management
Slide 36: Balanced Deposit Base
36 Savings & MMDA Transaction 31% 27% Jumbo CDs 23% Brokered CDs 11% Retail CDs 9% • Note: Deposit composition reflects regulatory holding company data Balanced Deposit Base Q3’26 Cost of Deposits: 2.69% $6.52B Q3’26 Total 36
Slide 37: Support of Strong Deposit Base
37 • Note: Deposit composition reflects regulatory holding company data Support of Strong Deposit Base Cost of Deposits 37 1.03% 0.43% 0.48% 2.34% 3.28% 2.96% 2.73% 2.68% 2.69% 0.00% 2.00% 4.00% 6.00% 2020 2021 2022 2023 2024 2025 Q1'26 Q2'26 Q3'26 Balance WAR Balance WAR Balance ($) Balance (%) WAR
Slide 38: Certificates of Deposit Maturities
38 • Note: Deposit composition reflects regulatory holding company data Certificates of Deposit Maturities 38 Time Deposit Maturities ($M) Brokered Deposit Maturities ($M) 3.82% 3.89% 3.90% 3.87% 3.97% $0 $200 $400 $600 $800 12/2026 03/2027 06/2027 09/2027 12/2027 3.92% 4.12% 0.00% 0.00% 0. 12/2026
Slide 39: Overview of Securities Portfolio
39 U.S. Treasuries 33% Mortgage-Backed Securities 38% Corporate Bonds 20% Other 9% Overview of Securities Portfolio $279.5M Q3’ 26 Total Q3’ 26 Yield on Securities: 4.45% 39
Slide 40: Interest Rate Sensitivity
40 Interest Rate Sensitivity At September 30, 2026 Change in Interest Rates Net Interest Income Year 1 Change (bps) Year 1 Forecast ($000) From Level +300 $313,603 6.8% +200 $307,671 4.8% +100 $301,449 2.6% -- $293,698 -- (100) $285,737 (2.7%) (200) $280,513 (4.5%) (300) $276,082 (6.0%) 40
Slide 41: Prudent Liquidity Management
41 FHLB Advances 3.8% Brokered Deposits 17.6% FHLB Unused Borrowing Capacity 17.9% FED Available Borrowing Capacity 29.4% Capacity for Additional Brokered Deposits 31.2% % of Total Liquidity Prudent Liquidity Management As of September 30, 2026, the Company had: • $150.3 million of outstanding advan
Slide 42: Appendix
42 Appendix
Slide 43: Notes and Reconciliation of U.S. GAAP and Non-GAAP Financial Measures
43 Notes and Reconciliation of U.S. GAAP and Non-GAAP Financial Measures In addition to results presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”), this press release contains certain non-GAAP financial measures, including pre-provision net
Slide 44: Notes and Reconciliation of U.S. GAAP and Non-GAAP Financial Measures (Cont.)
44 Notes and Reconciliation of U.S. GAAP and Non-GAAP Financial Measures (Cont.) 44 In addition to results presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”), this press release contains certain non-GAAP financial measures, including pre-pr
Slide 45: Notes and Reconciliation of U.S. GAAP and Non-GAAP Financial Measures (Cont.)
45 Notes and Reconciliation of U.S. GAAP and Non-GAAP Financial Measures (Cont.) 45 In addition to results presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”), this press release contains certain non-GAAP financial measures, including pre-pr
Slide 46: Notes and Reconciliation of U.S. GAAP and Non-GAAP Financial Measures (Cont.)
46 Notes and Reconciliation of U.S. GAAP and Non-GAAP Financial Measures (Cont.) 46 In addition to results presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”), this press release contains certain non-GAAP financial measures, including pre-pr
Slide 47: Executive Management Biographies
47 Executive Management Biographies Joseph Campanelli Chairman, President & CEO Christine Roberts SEVP & Chief Operating Officer JP Lapointe SEVP & Chief Financial Officer Mr. Campanelli has served as President and Chief Executive Officer of Needham Bank since joining the Bank in January 2017 and wa
Slide 48: Thank You
48 Thank You