Potomac, MD ZIP Codes
Potomac, Maryland has 3 ZIP codes: 2 for street addresses ( and ) and 1 for PO boxes ().
Your street decides which one you use.
Which Potomac ZIP code is my address in?
Street ranges from the Census Bureau, 2026. PO box and organization ZIP codes are not found by street. A new street may be missing: address not found?
Potomac ZIP code map
Tap or point to an area to see its ZIP code.Full-size map
20859 has no area on the map: it is a PO box or single-organization ZIP code. Dashed line: the Potomac Census outline.
Map: Census Bureau ZIP Code Tabulation Areas (2020) and place limits (2024).
All Potomac ZIP codes by type
| ZIP | Type and post office or station |
|---|---|
| 20817 | street delivery; mail may be addressed to Bethesda Westlake |
| 20854 | street delivery Potomac |
| 20859 | PO boxes at the Potomac post office Potomac |
Why your mail may say Potomac when you live outside it
Potomac ZIP codes also cover Travilah, Bethesda and Cabin John, so a letter addressed to Potomac can go to a home outside the town.
A ZIP code does not set your city, school district or tax. Montgomery County property records show which city you are in.
Potomac ZIP code questions
What is the main ZIP code for Potomac?
20854, the ZIP code of the main Potomac post office at 10221 River Rd.
Which Potomac ZIP codes are for PO boxes only?
20859. Mail to it goes to boxes at the post office, not to street addresses.
What county is Potomac in?
Montgomery County.
ZIP codes for towns near Potomac
More towns near Potomac: Silver Spring, Gaithersburg, Reston, West Falls Church, Oakton, Arlington, Olney, Sterling, Germantown.
Sources and last checked
USPS ZIP Locale Detail (October 1, 2026), GeoNames (CC BY 4.0), U.S. Census Bureau, HUD-USPS crosswalk.
Checked October 20, 2026. Sources · How we build our lists · Corrections