X0306 4 2021-08-20 0000944695 HANOVER INSURANCE GROUP, INC. THG 0001558946 Carlin Jane D C/O THE HANOVER INSURANCE GROUP, INC. 440 LINCOLN STREET WORCESTER MA 01653 1 0 0 0 Common Stock 2021-08-20 4 S 0 980 142.6612 D 0 D The price reported in Column 4 is a weighted average price. The shares were sold at multiple prices ranging from $142.56 to $142.79. The Reporting Person undertakes to provide The Hanover Insurance Group, Inc. ("THG"), any security holder of THG, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above. Does not include 5,929 shares held indirectly in a Rabbi Trust pursuant to deferral agreements. /s/ Matthew R. Frascella pursuant to Confirming Statement 2021-08-23