St. Mary’S County, located in the state of Maryland, contains a range of ZIP codes that are essential for mail delivery, demographics, mapping, and regional planning. Below is a complete list of ZIP codes associated with this county.

These ZIP codes help identify specific areas and communities within the county, ranging from small towns and villages to broader rural stretches. Whether you’re moving to St. Mary’S County, setting up a business, or analyzing demographic trends, understanding ZIP code distribution is an essential part of the process.

Zip code
20634
20692
20626
20620
20670
20659
20630
20609
20628
20635
20622
20684
20618
20686
20619
20653
20690
20660
20624
20674
20680
20650
20606
20656
20687
20621
20636
20667
20627

To know more about St. Mary’S County, click the button below:

St. Mary’S County Information

Use this tool to find your area details by using zip code.

ZIP Code to County

Note: Some ZIP codes may span across county borders and may be listed under more than one county. This is common in rural or low-population areas where ZIP code regions are broader.

Source: Data compiled from official county records, USPS ZIP code data, and the United States Census Bureau.

Frequently Asked Questions

How many ZIP codes are in St. Mary’S County County?

There are approximately 29 ZIP codes in this county. Check the table above for the complete list.

Do ZIP codes in St. Mary’S County overlap with other counties?

Yes, some ZIP codes may span more than one county. This is especially common in less populated or rural areas.