- Salisbury (1,034 Companies)
- Salisbury Beach (1 Company)
- Sandisfield (45 Companies)
- Sandwich (1,346 Companies)
- Saugus (2,545 Companies)
- Savoy (28 Companies)
- Scituate (1,146 Companies)
- Seabrook (1 Company)
- Seekonk (1,809 Companies)
- Sharon (819 Companies)
- Sheffield (264 Companies)
- Shelburne Falls (397 Companies)
- Shelburne Fls (1 Company)
- Sheldonville (2 Companies)
- Sherborn (237 Companies)
- Shirley (362 Companies)
- Shrewsbury (2,462 Companies)
- Shutesbury (36 Companies)
- Siasconset (16 Companies)
- Silver Spring (1 Company)
- Somerset (1,114 Companies)
- Somerville (4,672 Companies)
- South Attleboro (36 Companies)
- South Barre (10 Companies)
- South Boston (1,874 Companies)
- South Carver (2 Companies)
- South Chatham (131 Companies)
- South Dartmouth (662 Companies)
- South Deerfield (575 Companies)
- South Dennis (763 Companies)
- South Easton (1,242 Companies)
- South Egremont (34 Companies)
- South Grafton (155 Companies)
- South Hadley (955 Companies)
- South Hamilton (426 Companies)
- South Harwich (2 Companies)
- South Lancaster (5 Companies)
- South Lee (2 Companies)
- South Orleans (6 Companies)
- South Walpole (22 Companies)
- South Waltham (1 Company)
- South Wellfleet (3 Companies)
- South Weymouth (1,156 Companies)
- South Yarmouth (1,083 Companies)
- Southampton (314 Companies)
- Southboro (4 Companies)
- Southborough (901 Companies)
- Southbridge (1,250 Companies)
- Southfield (18 Companies)
- Southwick (673 Companies)
- Spencer (741 Companies)
- Springfield (11,162 Companies)
- Sterling (544 Companies)
- Stockbridge (164 Companies)
- Stoneham (1,891 Companies)
- Stoughton (2,975 Companies)
- Stow (424 Companies)
- Sturbridge (765 Companies)
- Sudbury (1,426 Companies)
- Sunderland (170 Companies)
- Sutton (594 Companies)
- Swampscott (960 Companies)
- Swansea (1,389 Companies)
- Taunton (3,794 Companies)
- Teaticket (27 Companies)
- Templeton (183 Companies)
- Tewksbury (2,258 Companies)
- Thorndike (20 Companies)
