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ZIP Code 20854 — Potomac, MD

20854 is a standard (street delivery) ZIP code serving Potomac, Maryland, in Montgomery County. To mail something here you only need these five digits — but the four-digit extension narrows delivery to a single point, and it is what USPS bulk postage discounts are priced on.

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ZIP code 20854 at a glance

ZIP code20854
Primary cityPotomac
StateMaryland (MD)
CountyMontgomery FIPS 24031
ZIP typeStandard (street delivery)
Time zoneAmerica/New_York
Population50,498
Coordinates39.034130, -77.221490

How ZIP+4 works in 20854

The four digits after the hyphen encode a delivery segment inside 20854. In practice one segment usually means:

That is why 20854 has no single ZIP+4: two neighbors across the street from each other usually have different ones. Enter a street address above and we will return the exact nine-digit code along with the standardized USPS address format.

Nearby ZIP codes

Showing the closest twelve. See every ZIP code within 25 miles of 20854.

ZIPCityDistance
20850 Rockville, MD 4.5 mi
22066 Great Falls, VA 4.6 mi
20817 Bethesda, MD 4.6 mi
20852 Rockville, MD 5.3 mi
20818 Cabin John, MD 5.3 mi
22102 Mclean, VA 5.7 mi
20878 Gaithersburg, MD 5.7 mi
20812 Glen Echo, MD 6.2 mi
20851 Rockville, MD 6.2 mi
20892 Bethesda, MD 6.7 mi
20814 Bethesda, MD 6.7 mi
20896 Garrett Park, MD 6.8 mi

Questions about 20854

What is the ZIP+4 code for 20854?

20854 is the five-digit ZIP code. The ZIP+4 adds four more digits that identify a specific delivery point — usually one side of a city block, a single building, or a group of PO boxes. Because those four digits change from address to address within 20854, you need to look up a specific street address to get them.

What city is 20854?

20854 is assigned to Potomac, Maryland, in Montgomery County.

Do I need to use the ZIP+4?

It is optional for ordinary mail, but it speeds up sorting and it is required for most USPS bulk-mail postage discounts. Many address-verification and e-commerce systems also use ZIP+4 to confirm a delivery point exists.

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