Massachusetts frost dates: B
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Babson Park | Apr 26 | Oct 12 | 169 d | 6b |
| Baldwinville | May 6 | Oct 1 | 148 d | 5b |
| Barnstable | Apr 22 | Oct 28 | 189 d | 7a |
| Barre | May 12 | Oct 1 | 142 d | 6a |
| Becket | May 7 | Oct 3 | 149 d | 6a |
| Bedford | Apr 27 | Oct 13 | 169 d | 6b |
| Belchertown | May 3 | Oct 14 | 164 d | 6a |
| Bellingham | Apr 30 | Oct 9 | 162 d | 6b |
| Belmont | Apr 19 | Oct 23 | 187 d | 6b |
| Berkley | May 2 | Oct 8 | 159 d | 6b |
| Berkshire | May 5 | Oct 5 | 153 d | 5b |
| Berlin | May 2 | Oct 6 | 157 d | 6b |
| Bernardston | May 1 | Oct 11 | 163 d | 5b |
| Beverly | Apr 24 | Oct 17 | 176 d | 6b |
| Billerica | Apr 27 | Oct 13 | 169 d | 6b |
| Blackstone | Apr 22 | Oct 19 | 180 d | 6b |
| Blandford | Apr 28 | Oct 17 | 172 d | 6a |
| Bolton | May 2 | Oct 6 | 157 d | 6b |
| Bondsville | May 3 | Oct 14 | 164 d | 6a |
| Boston | Apr 4 | Nov 9 | 219 d | 7a |
| Boxborough | May 2 | Oct 6 | 157 d | 6a |
| Boxford | May 3 | Oct 8 | 158 d | 6b |
| Boylston | Apr 23 | Oct 21 | 181 d | 6a |
| Braintree | Apr 18 | Oct 26 | 191 d | 6b |
| Brant Rock | Apr 15 | Nov 1 | 200 d | 7a |
| Brewster | Apr 13 | Nov 4 | 205 d | 7b |
| Bridgewater | May 1 | Oct 9 | 161 d | 6b |
| Brighton | Apr 19 | Oct 23 | 187 d | 6b |
| Brimfield | Apr 28 | Oct 15 | 170 d | 6a |
| Brockton | Apr 22 | Oct 19 | 180 d | 6b |
| Brookfield | Apr 28 | Oct 15 | 170 d | 6a |
| Brookline | Apr 19 | Oct 23 | 187 d | 6b |
| Brookline Village | Apr 19 | Oct 23 | 187 d | 6b |
| Bryantville | Apr 15 | Nov 1 | 200 d | 6b |
| Buckland | May 17 | Oct 1 | 137 d | 5b |
| Burlington | Apr 25 | Oct 17 | 175 d | 6b |
| Buzzards Bay | Apr 26 | Oct 26 | 183 d | 7a |
| Byfield | May 3 | Oct 8 | 158 d | 6b |