X0306 4 2020-06-11 0 0001667161 Randolph Bancorp, Inc. RNDB 0001429021 Parent William M C/O RANDOLPH BANCORP INC. 10 CABOT PLACE STOUGHTON MA 02072 1 1 0 0 President and CEO Common Stock 2020-06-11 4 P 0 2500 9.30 A 22686 I By IRA Common Stock 2020-06-12 4 P 0 1800 9.166 A 24486 I By IRA Common Stock 10324 D Stock Option (Right to Buy) 8.78 2030-03-31 Common Stock 29412 29412 D Represents a weighted average purchase price per share. These shares were purchased in multiple transactions at prices ranging from $9.00 to $9.20. The Reporting Person has provided the Issuer, and undertakes to provide to the staff of the Securities and Exchange Commission or any security holder of the Issuer, upon request, full information regarding the number of shares purchased at each separate price within the range. Includes 10,000 shares of restricted stock which vest in five equal annual installments beginning on April 1, 2021. The options vest in five equal annual installments beginning on April 1, 2021. /s/ William M. Parent 2020-06-15