Voter guide: What you need to know about the Massachusetts 2026 primary electionThe Massachusetts state primary is set for Tuesday, Sept. 1. You could also apply online (here) or email/fax your application to your local election office. Ballots must reach a drop box or your local election office by 8 p.m. on Sept. 1 (Election Day). Every town and city has their own hours and locations, so check your local election office for details. Vote on Election DayThe official Election Day for the state primary is Sept. 1.