Exhibit 3.1

Delaware The First State Page 1 2079617 8100X Authentication: 203364374 SR# 20232112872 Date: 05-17-23 You may verify this certificate online at corp.delaware.gov/authver.shtml I, JEFFREY W. BULLOCK, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO HEREBY CERTIFY THE ATTACHED ARE TRUE AND CORRECT COPIES OF ALL DOCUMENTS FILED FROM AND INCLUDING THE RESTATED CERTIFICATE OR A MERGER WITH A RESTATED CERTIFICATE ATTACHED OF “WATTS WATER TECHNOLOGIES, INC.” AS RECEIVED AND FILED IN THIS OFFICE. THE FOLLOWING DOCUMENTS HAVE BEEN CERTIFIED: RESTATED CERTIFICATE, FILED THE TWENTY-EIGHTH DAY OF AUGUST, A.D. 1986, AT 8:40 O`CLOCK A.M. CERTIFICATE OF AMENDMENT, FILED THE EIGHTEENTH DAY OF OCTOBER, A.D. 1990, AT 12 O`CLOCK P.M. CERTIFICATE OF AMENDMENT, FILED THE SIXTEENTH DAY OF OCTOBER, A.D. 1991, AT 4:30 O`CLOCK P.M. CERTIFICATE OF AMENDMENT, FILED THE EIGHTEENTH DAY OF OCTOBER, A.D. 1994, AT 12 O`CLOCK P.M. CERTIFICATE OF OWNERSHIP, FILED THE TWENTIETH DAY OF DECEMBER, A.D. 2002, AT 12:30 O`CLOCK P.M.

Delaware The First State Page 2 2079617 8100X Authentication: 203364374 SR# 20232112872 Date: 05-17-23 You may verify this certificate online at corp.delaware.gov/authver.shtml CERTIFICATE OF OWNERSHIP, CHANGING ITS NAME FROM "WATTS INDUSTRIES, INC." TO "WATTS WATER TECHNOLOGIES, INC.", FILED THE FOURTEENTH DAY OF OCTOBER, A.D. 2003, AT 2:39 O`CLOCK P.M. AND I DO HEREBY FURTHER CERTIFY THAT THE EFFECTIVE DATE OF THE AFORESAID CERTIFICATE OF OWNERSHIP IS THE FIFTEENTH DAY OF OCTOBER, A.D. 2003 AT 12:01 O'CLOCK A.M. CERTIFICATE OF AMENDMENT, FILED THE SEVENTEENTH DAY OF MAY, A.D. 2019, AT 9:50 O`CLOCK A.M. CERTIFICATE OF AMENDMENT, FILED THE SEVENTEENTH DAY OF MAY, A.D. 2023, AT 10:07 O`CLOCK A.M.