21770 Post Office

Find 21770 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.


Monrovia Post Office 4411 Green Valley Road Monrovia MD 21770 301-865-5432


New Market Post Office 168 West Main Street New Market MD 21774 2.7 miles from 21770 301-865-3333

Damascus Post Office 26400 Woodfield Road Damascus MD 20872 5.0 miles from 21770 301-253-3781

Mount Airy Post Office 505 Windy Knoll Drive Mount Airy MD 21771 5.9 miles from 21770 301-829-1199

Clarksburg Post Office 22505 Gateway Center Drive Clarksburg MD 20871 8.6 miles from 21770 301-540-0856

Buckeystown Post Office 4001 Buckeystown Pike Frederick MD 21704 9.2 miles from 21770 301-874-5294

Frederick Post Office 201 East Patrick Street Frederick MD 21701 9.2 miles from 21770 301-662-2131

Libertytown Post Office 11941 Main Street Frederick MD 21701 9.2 miles from 21770 301-898-7156

Lisbon Post Office 1280 Hopkins Alley Lisbon MD 21765 10.0 miles from 21770 410-489-7177

College Estates Post Office 1301 West 7th Street Frederick MD 21702 10.3 miles from 21770 301-662-6115

Walkersville Post Office 7 East Frederick Street Walkersville MD 21793 10.4 miles from 21770 301-845-8342

Woodbine Post Office 7623 Woodbine Road Woodbine MD 21797 10.6 miles from 21770 410-795-9596

Barnesville Post Office 22110 Beallsville Road Barnesville MD 20838 11.1 miles from 21770 301-972-8153

Laytonsville Post Office 6830 Olney Laytonsville Road Laytonsville MD 20882 11.8 miles from 21770 301-208-3736

Boyds Post Office 15300 Barnesville Road Boyds MD 20841 11.8 miles from 21770 301-972-9527

Adamstown Post Office 5537 Mountville Road Adamstown MD 21710 12.0 miles from 21770 301-874-5429

Germantown Post Office 12774 Wisteria Drive Germantown MD 20874 12.1 miles from 21770 301-428-0460

Montgomery Village Post Office 10079 Stedwick Road Montgomery Village MD 20886 12.6 miles from 21770 301-208-3716

Woodsboro Post Office 602 South Main Street Woodsboro MD 21798 12.7 miles from 21770 301-845-8408

Dickerson Post Office 22145 Dickerson Road Dickerson MD 20842 12.8 miles from 21770 301-428-8243

About Post Offices

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.