ZIP Codes in Maryland
Maryland's ZIP codes cover a small but geographically varied state, wedged between Washington, D.C. and the Chesapeake Bay, with around 6.2 million residents split between Baltimore's urban core, the DC-adjacent suburbs in the state's center, and a rural Eastern Shore across the bay. Few states pack as much economic and geographic diversity into such a compact footprint.
How ZIP Codes Are Organized Across the State
Maryland's ZIP codes fall within the 20600–21999 range under the USPS system. The DC suburbs, including Bethesda and Silver Spring, occupy the lower end around 208xx–209xx, Baltimore sits near 212xx, and Annapolis, the state capital, carries codes closer to 214xx. The Eastern Shore, across the Chesapeake Bay, pushes toward the upper end around 216xx–218xx.
Maryland's Major Metro Areas by Population
The chart below shows how population splits between the Baltimore metro area and the DC suburbs, Maryland's two dominant population centers.
Baltimore's ZIP codes cover Maryland's largest city, a historic port with a strong healthcare and biotech presence anchored by Johns Hopkins University and its associated hospital system. The Maryland suburbs of Washington, D.C., including Bethesda, Silver Spring, and Rockville, carry some of the highest median incomes in the entire country, driven heavily by federal government employment and the region's dense concentration of contractors and agencies. For a broader comparison, our full US ZIP code directory shows how Maryland's ranges fit alongside every other state.
The DC Suburbs and Montgomery County
Maryland's DC-adjacent suburbs sit right along the border with Washington, D.C. itself, and daily commuting between the two blurs the practical distinction between city and suburb for many residents. ZIP codes here reflect some of the most expensive real estate in the state, driven by proximity to federal jobs and the Metro rail system connecting directly into the capital.
The Eastern Shore and Chesapeake Bay
Across the Chesapeake Bay, Maryland's Eastern Shore feels worlds apart from the busy DC and Baltimore corridors - a mostly rural, agricultural region with a strong seafood industry built around blue crab and oysters. This area shares the Delmarva Peninsula with Delaware and Virginia, and the postal geography on both sides reflects a similar mix of farmland and small waterfront towns.
Why ZIP Codes Matter Beyond Mail
In Maryland, ZIP codes carry particular weight around Baltimore and the DC suburbs, where boundaries can signal significant differences in school district quality and commute time to federal jobs. The state's biotech and healthcare industry, concentrated heavily around Baltimore and the I-270 corridor near Bethesda, relies on ZIP-level data for site selection and workforce planning. And Chesapeake Bay watermen and seafood processors use ZIP codes to coordinate the Eastern Shore's crab and oyster industry logistics.
Border Regions and Neighboring States
Maryland shares borders with several states and the District of Columbia. To the west, the border with West Virginia narrows into Maryland's distinctive panhandle. To the north, Pennsylvania connects into the broader mid-Atlantic corridor near Baltimore. And to the south, Virginia shares the Eastern Shore's Delmarva Peninsula geography.
Finding the Right ZIP Code
Use the list below to browse Maryland's ZIP codes by city, county, or population - sorted so the most populous areas surface first. Each entry links through to a detailed page with additional demographic data. If you're trying to identify the ZIP code for a specific address rather than browsing by city, the search tool at the top of this page will get you there faster than scrolling through the full list.
Frequently Asked Questions
How many ZIP codes does Maryland have?
Maryland has several hundred ZIP codes, concentrated most heavily around Baltimore and the DC suburbs, with far fewer covering the rural Eastern Shore.
What ZIP code range does Maryland use?
Maryland ZIP codes generally fall between 20600 and 21999, with the DC suburbs toward the lower end and the Eastern Shore further along the range.
Which Maryland city has the most ZIP codes?
Baltimore and the DC-adjacent suburbs together account for the vast majority of Maryland's ZIP codes, given how heavily the state's population concentrates in these two corridors.
Can I look up a Maryland ZIP code by city name?
Yes, use the search tool on this page or browse the full list below, which is organized by city and sorted by population.
Whether you're relocating to the DC suburbs, researching property in Baltimore, or simply trying to pin down the right ZIP code for a specific Maryland address, the data below covers every corner of the state - from the Pennsylvania line to the Eastern Shore.