| County | FIPS |
|---|---|
| Barnstable County | 25001 |
| Berkshire County | 25003 |
| Bristol County | 25005 |
| Dukes County | 25007 |
| Essex County | 25009 |
| Franklin County | 25011 |
| Hampden County | 25013 |
| Hampshire County | 25015 |
| Middlesex County | 25017 |
| Nantucket County | 25019 |
| Norfolk County | 25021 |
| Plymouth County | 25023 |
| Suffolk County | 25025 |
| Worcester County | 25027 |