Sales tax in St. Mary's County, Maryland
The sales tax rate in St. Mary's County, Maryland is 6%. That is a 6% state rate, with no county rate on top: St. Mary's County levies none, and it is the same at every address in the county. That rate was read from Maryland's own published schedule and checked on August 30, 2026.
What is the sales tax rate in St. Mary's County?
| Maryland state rate | 6% |
|---|---|
| Combined rate | 6% |
How much sales tax is that on a purchase in St. Mary's County?
At 6%, a $100 purchase carries $6.00 in sales tax and a $1,000 purchase $60.00. That is general merchandise; Maryland taxes some categories, often groceries, differently, as the note below explains.
Every county in Maryland has the same 6% floor. See every Maryland county.
Sales tax in counties next to St. Mary's County
St. Mary's County borders 6 counties, 2 of them in another state. The lowest rate next door is 5.3% in Northumberland County, VA, which is $7.00 less on a $1,000 purchase than St. Mary's County's rate.
| County | Combined sales tax |
|---|---|
| Calvert County, MD | 6% |
| Charles County, MD | 6% |
| Dorchester County, MD | 6% |
| Somerset County, MD | 6% |
| St. Mary's County, MD (this county) | 6% |
| Northumberland County, VA | 5.3% |
| Westmoreland County, VA | 5.3% |
Why the rate here is not the whole story
No local sales taxes anywhere in the state; groceries and prescription/OTC drugs are exempt.
How do I find the exact rate for an address in St. Mary's County?
Use Maryland's own address lookup.
Who has to collect sales tax in St. Mary's County?
Any seller with a physical presence in Maryland collects at the rate for the address of the sale; a remote seller does once it passes Maryland's economic nexus threshold. Maryland sales tax covers the statewide rules and what is exempt.
Work out your own numbers
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Sales tax calculator
Tax on a specific purchase at this county's rate, and the total you will actually pay.
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Do you have to collect?
Whether your sales into Maryland cross its economic nexus threshold. A different question from the rate.
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Property tax in St. Mary's County
The other local tax: effective rate and median bill for this county.
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Sales tax by county
Every US county, and how Maryland compares with the rest of the country.
Sources
- St. Mary's County rates: Comptroller of Maryland / Tax Foundation, State and Local Sales Tax Rates (Jan. 2026)
- Collected and verified August 30, 2026. Confidence: S on the rate components (P read on a primary agency page, S strong but indirect, U unverified).