| Transit agency | City | Vehicles operated directly | Website |
|---|---|---|---|
| Massachusetts Bay Transportation Authority | Boston | 999 | Official site |
| Worcester Regional Transit Authority | Worcester | 54 | Official site |
| Woods Hole, Martha's Vineyard and Nantucket Steamship Authority | Falmouth | 25 | Official site |
| The Mashpee Wampanoag Tribe | Mashpee | 4 | — |
| Town of Bedford | Bedford | 2 | Official site |
| Berkshire Regional Transit Authority | Pittsfield | 0 | Official site |
| Brockton Area Transit Authority | Brockton | 0 | Official site |
| Cape Ann Transportation Authority | Gloucester | 0 | Official site |
| Cape Cod Regional Transit Authority | Hyannis | 0 | Official site |
| City of Beverly | Beverly | 0 | — |
| Franklin Regional Transit Authority | Greenfield | 0 | Official site |
| Greater Attleboro-Taunton Regional Transit Authority | Taunton | 0 | Official site |
| Lowell Regional Transit Authority | Lowell | 0 | Official site |
| Martha's Vineyard Transit Authority | Edgartown | 0 | Official site |
| Merrimack Valley Regional Transit Authority | Haverhill | 0 | Official site |
| MetroWest Regional Transit Authority | Framingham | 0 | Official site |
| Montachusett Regional Transit Authority | Fitchburg | 0 | Official site |
| Nantucket Regional Transit Authority | Nantucket | 0 | Official site |
| Pioneer Valley Transit Authority | Springfield | 0 | Official site |
| Southeastern Regional Transit Authority | New Bedford | 0 | Official site |
| Town of Lexington | Lexington | 0 | Official site |
Largest first by vehicles operated directly, as each employer reports it to its federal registry.
Source: Federal Transit Administration, National Transit Database 2024 — Reporter Agency Information. Data captured September 30, 2026.