X0407 4 2023-03-31 0000944695 HANOVER INSURANCE GROUP, INC. THG 0001572984 Lowsley Denise C/O THE HANOVER INSURANCE GROUP, INC. 440 LINCOLN STREET WORCESTER MA 01653 0 1 0 0 Executive Vice President 0 Common Stock 2023-03-31 4 A 0 13.832 0 A 4031.161 D Grant of restricted stock units under the Issuer's 2014 Long-Term Incentive Plan or the 2022 Long-Term Incentive Plan, as applicable, upon the accrual of dividend rights associated with restricted stock units previously granted by the Issuer. Such units vest on the third anniversary of the date of grant of the underlying restricted stock units. Due to a clerical error, the number reported in column 5 of the Form 4 filed on March 1, 2023 was overstated by 0.063 shares. All other line items in the Form 4 filed on March 1, 2023 are correct. The amount of securities beneficially owned by the reporting person reported in column 5 of this Form 4 corrects the previous error. /s/ Walter H. Stowell pursuant to Confirming Statement 2023-04-04