Narragansett Bancorp, Inc.

The following tables summarize historical data for Narragansett Financial Corporation and pro forma data for Narragansett Bancorp, Inc. at and for the three months ended March 31, 2026 and at and for the year ended December 31, 2025. This information is based on assumptions set forth below and in the tables and related footnotes, and should not be used as a basis for projections of market value of the shares of common stock following the offering.

We calculated the pro forma consolidated net income of Narragansett Bancorp, Inc. for each period as if the shares of common stock had been sold at the beginning of the period and the net proceeds had been invested at 3.92% (2.94% on anafter-tax basis), which is equal to the yield on the five-year U.S. Treasury Note as of March 31, 2026. In light of current interest rates, we consider this rate to more accurately reflect the pro forma reinvestment rate than the arithmetic average method, which assumes reinvestment of the net proceeds at a rate equal to the average of the yield on interest-earning assets and the cost of deposits for those periods.

We further believe that the reinvestment rate is factually supportable because:

We calculated historical and pro forma per share amounts by dividing historical and pro forma amounts of net income and stockholders’ equity by the indicated number of shares of common stock. For pro forma calculations, we adjusted these figures to give effect to the shares of common stock purchased by the employee stock ownership plan. We computed per share amounts for each period as if the common stock was outstanding at the beginning of the periods, but we did not adjust per share historical or pro forma stockholders’ equity to reflect the earnings on the estimated net proceeds.

The pro forma tables give effect to the implementation of a stock-based benefit plan. We have assumed that the stock-based benefit plan will acquire an amount of common stock equal to 4% of the aggregate number of shares of common stock sold in the offering and contributed to the charitable foundation at the same price for which the shares of common stock were sold in the offering. We assume that shares of common stock are granted under the plan in awards that vest over a five-year period.

We have also assumed that the stock-based benefit plan will grant options to acquire common stock equal to 10% of the aggregate number of shares of common stock sold in the offering and contributed to the charitable foundation. In preparing the following table, we also assumed that stockholder approval was obtained, that the exercise price of the stock options and the market price of the stock at the date of grant were $10.00 per share and that the stock options had a term of ten years and vested over five years. We applied the Black-Scholes option pricing model to estimate a grant-date fair value of $4.64 for each option. In addition to the terms of the options described above, the Black-Scholes option pricing model incorporated an estimated volatility rate of 25.20% for the common stock based on an index of publicly traded financial institutions and financial institution holding companies, no dividend yield, an expected option life of 10 years and a risk-free interest rate of 4.30%. The plan of reorganization provides that we may grant awards of stock or options under one or more stock benefit plans in an amount up to 25% of the shares of common stock held by persons other than Narragansett Financial Corporation.

As disclosed under “How We Intend to Use the Proceeds from the Offering,” Narragansett Bancorp, Inc. intends to contribute 50% of the net proceeds from the offering to BayCoast Bank. Narragansett Bancorp, Inc. will use a portion of the proceeds it retains to make a loan to the employee stock ownership plan and retain the rest of the proceeds for future use.

The pro forma tables do not give effect to:

The following pro forma information may not represent the financial effects of the offering at the date on which the offering actually occurs and you should not use the tables to indicate future results of operations. Pro forma stockholders’ equity represents the difference between the stated amounts of assets and liabilities of Narragansett Bancorp, Inc., computed in accordance with GAAP. We did not increase or decrease stockholders’ equity to reflect the difference between the carrying value of loans and other assets and their market value. Pro forma stockholders’ equity is not intended to represent the fair market value of the common stock, and may be different than the amounts that would be available for distribution to stockholders if we were liquidated.** **

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