21791 Post Office

Find 21791 post offices and USPS mailing boxes. Post offices provide information on bulk mail services, domestic mail delivery, international shipping, change of address, mail forwarding, PO boxes, and passport services.


Union Bridge Post Office 111 Penrose Street Union Bridge MD 21791 410-775-2510


New Windsor Post Office 204 Maple Avenue New Windsor MD 21776 4.4 miles from 21791 410-635-2151

Libertytown Post Office 11941 Main Street Frederick MD 21701 4.8 miles from 21791 301-898-7156

Ladiesburg Post Office 12509 Woodsboro Pike Keymar MD 21757 5.0 miles from 21791 301-845-2956

Keymar Post Office 6747 Middleburg Road Keymar MD 21757 5.5 miles from 21791 410-775-2262

New Midway Post Office 12048 Woodsboro Pike Keymar MD 21757 6.1 miles from 21791 301-845-2145

Woodsboro Post Office 602 South Main Street Woodsboro MD 21798 6.7 miles from 21791 301-845-8408

Rocky Ridge Post Office 13516 Motters Station Road Rocky Ridge MD 21778 8.6 miles from 21791 301-271-4920

Taneytown Post Office 13 Middle Street Taneytown MD 21787 8.7 miles from 21791 410-756-6411

Walkersville Post Office 7 East Frederick Street Walkersville MD 21793 9.3 miles from 21791 301-845-8342

New Market Post Office 168 West Main Street New Market MD 21774 11.5 miles from 21791 301-865-3333

Mount Airy Post Office 505 Windy Knoll Drive Mount Airy MD 21771 11.5 miles from 21791 301-829-1199

Westminster Post Office 345 Woodward Drive Westminster MD 21157 11.6 miles from 21791 410-848-4805

Monrovia Post Office 4411 Green Valley Road Monrovia MD 21770 13.0 miles from 21791 301-865-5432

Thurmont Post Office 110 Water Street Thurmont MD 21788 13.3 miles from 21791 301-271-2226

Woodbine Post Office 7623 Woodbine Road Woodbine MD 21797 13.6 miles from 21791 410-795-9596

Emmitsburg Post Office 305 South Seton Avenue Emmitsburg MD 21727 13.8 miles from 21791 301-447-2655

Frederick Post Office 201 East Patrick Street Frederick MD 21701 14.2 miles from 21791 301-662-2131

College Estates Post Office 1301 West 7th Street Frederick MD 21702 14.3 miles from 21791 301-662-6115

Lisbon Post Office 1280 Hopkins Alley Lisbon MD 21765 15.0 miles from 21791 410-489-7177

What Change of Address options are available?

Customers can request a temporary or permanent Change of Address either online or in person at the Post Office using PS Form 3575. The online application for Change of Address has a $1.00 identity validation fee.

Is it possible to insure mail and items sent via the USPS?

Yes. Standard mail can be insured for up to $5,000 for an additional fee. Registered mail items can be insured for up to $50,000.

What is the USPS Office of Inspector General?

The Office of Inspector General (OIG) is a division within the USPS responsible for ensuring the integrity and accountability of the postal service. It conducts investigations to safeguard the postal system and performs audits and reviews.