Castine Post Office

Post office

43 Main St, Castine, ME 04421

(207) 326-8551

This facility does not require an appointment to accept passport applications.

Appointment required

Hours and addresses come from the State Department listing, updated November 2, 2026.

Book at USPS Directions Facilities in Castine Facilities in Maine

Castine Post Office accepts new U.S. passport applications in person in Castine, ME. First-time and child visits are booked on the USPS scheduler. Search ZIP 04421. How to apply · How to renew