| District ID | 3rd District |
| Representative | Lori Trahan |
| Party Affiliation | Democrat |
| Partisan Voting Index (PVI) | D+9 |
| 01886 |
| 01879 |
| 01876 |
| 01863 |
| 01862 |
| 01860 |
| 01854 |
| 01852 |
| 01851 |
| 01850 |
| 01845 |
| 01844 |
| 01843 |
| 01841 |
| 01840 |
| 01835 |
| 01832 |
| 01830 |
| 01827 |
| 01826 |
| 01824 |
| 01821 |
| 01775 |
| 01773 |
| 01752 |
| 01749 |
| 01742 |
| 01741 |
| 01740 |
| 01730 |
| 01720 |
| 01719 |
| 01718 |
| 01523 |
| 01510 |
| 01503 |
| 01475 |
| 01474 |
| 01473 |
| 01469 |
| 01464 |
| 01463 |
| 01462 |
| 01460 |
| 01453 |
| 01451 |
| 01450 |
| 01440 |
| 01436 |
| 01434 |
| 01432 |
| 01431 |
| 01430 |
| 01420 |