
Frederick County · Maryland
ZIP code 21770
- Population
- 7,815
- Median income
- $184,464
- Median home
- $599,700
- Sales tax
- 6%
ZCTA residents
Household, past 12 months
Owner-occupied value
Maryland state rate
Quick answer
ZIP 21770 sits in Frederick County, Maryland and is home to 7,815 people. Median household income is $184,464, the median home is worth $599,700 and median gross rent is —. 98% of households own their home, and purchases are taxed at 6% (Maryland state rate).
- County
- Frederick County
- State
- Maryland (MD)
- Area codes
- Not published
- Metro area
- Outside covered metros
FIPS 24021
477 ZIPs covered
No NANPA match for this ZIP
Rate jurisdiction used for tax
The numbers for 21770
American Community Survey 2019-2023 ACS 5-year estimates for this ZCTA.
- Population
- 7,815ZIP 21770 residents
- Median household income
- $184,464Past 12 months, inflation adjusted
- Median home value
- $599,700Owner-occupied units
- Median gross rent
- —Rent plus utilities, monthly
- Median age
- 41.2 yrsAll residents
- Homeownership rate
- 98%Owner-occupied households
ZIP 21770 in context
How this area compares with national benchmarks.
ZIP 21770 is a mid-size town in Frederick County, Maryland, with 7,815 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates, which places it #195 of 477 ranked by population — larger than 59% of them. The median age here is 41.2 years against 39.1 nationally, a slightly older profile than the country as a whole. Places under 65,000 residents only appear in the five-year release, never the one-year file, so these values pool sixty months of responses and lag the current year by design.
Households in ZIP 21770 earn a median of $184,464 a year, 134.9% above the national figure of $78,538. This figure covers the household, not the worker: two people on ordinary wages at one address outrank a single professional in the same table. Poverty reaches 1.4% of residents here, less than half the 12.4% national rate.
The typical owner-occupied home in ZIP 21770 is valued at $599,700, 97.7% above the national figure, while median gross rent runs not published a month. The home-price-to-income ratio works out to 3.3×, against roughly 3.9× nationally, so buying is easier here than in the average US market. 98% of occupied homes are owner-occupied versus 65% nationally, an owner-dominated market where rental listings are scarce and rent medians rest on a thin sample. The rent line includes utilities paid by the tenant, a definition worth remembering when comparing it against a landlord's quoted rate.
The Census withheld gross rent for ZIP 21770 because the sample was too thin to publish at this geography. Those values were suppressed at the source, not lost in our dataset, and we do not model a replacement. Everything else on this page comes straight from the ACS 2019-2023 ACS 5-year tables.
Reading ZIP 21770 in context
How 21770 sits inside Frederick County and Maryland.
ZIP 21770 is tabulated inside Frederick County, Maryland, one of 28 ZIP areas the Census publishes for that county and 477 across Maryland. Population sits in the small-town band, typically one main street plus the addresses that feed into it. County assignment on this page follows the largest share of the ZIP's land area, which matters where a delivery route crosses a county line: mail addressed to 21770 can be handled by a post office in a neighbouring county even though the tabulation area is filed here.
Against its own county, 21770 reports a median household income of $184,464, 44% above the $128,504 county median, and 77% above the $104,338 typical MD ZIP. Owner-occupied homes are valued at a median of $599,700, 39% above the county figure and 50% above the statewide ZIP median. Rent is reported gross — the contract amount plus tenant-paid utilities — at not published a month, which is why it reads higher than the advertised rent on a listing for the same unit.
Maryland charges 6% statewide, and no local sales tax is layered on top, so the state rate is the full amount collected in 21770.
Everything above comes from the Census Bureau American Community Survey 2019-2023 ACS 5-year estimates for this ZIP Code Tabulation Area, with sales tax rates traced to the state revenue agency. Five-year estimates pool sixty months of responses, so they are stable enough to compare 21770 with its neighbours but always trail the current year, and any value the Census suppressed for sample size is shown as unpublished rather than filled in with a model.
Sales tax in 21770
What a purchase inside this ZIP costs at checkout.
Maryland levies 6% statewide with no local add-ons. Check the county page for the local component before you quote a price.
Affordability in this ZIP
Derived from the Census medians above — indicative, not an offer.
A rent burden above 30% is the federal threshold for cost-burdened households, and a price-to-income multiple above 4× is generally considered a stretched housing market. The mortgage figure is principal and interest only — taxes, insurance and HOA dues are extra.
How 21770 compares
ZIP 21770 against the median ZIP in Frederick County and across Maryland.
| Measure | ZIP 21770 | County median | State median | vs state |
|---|---|---|---|---|
| Median household income | $184,464 | $128,504 | $104,338 | +77% |
| Median home value | $599,700 | $430,000 | $401,000 | +50% |
| Median gross rent | — | $1,604 | $1,600 | — |
| Population | 7,815 | 5,680 | 4,995 | +56% |
Medians are computed across the 28 ZIP areas in Frederick County and the 477 ZIP areas in Maryland.
Statewide rank
Where this ZIP places among all 477 Maryland ZIP areas.
- Income
- #31
- Home value
- #61
- Population
- #195
richer than 93% of 428 state ZIPs
above 86% of 425 state ZIPs
larger than 59% of 477 state ZIPs
Comparable ZIP codes
Maryland ZIP areas with almost the same household income.
Nearby ZIP codes
Other ZIP codes filed under Frederick County.
Adjacent ZIP Codes
Other ZIP codes in Frederick County, Maryland.
ZIP 21770 questions
Common questions about this ZIP code.
- Where is ZIP code 21770?
- ZIP 21770 lies mostly in Frederick County, Maryland. County assignment follows the largest share of land area, so a ZIP straddling a county line is filed under its dominant county.
- What sales tax do I pay in 21770?
- Maryland charges 6% statewide.
- Is 21770 expensive to live in?
- Median rent runs — a month, and the median home is worth $599,700 — +50% against the typical Maryland ZIP.
- Is a ZCTA the same as a postal ZIP code?
- Not exactly. The Census builds ZIP Code Tabulation Areas from the ZIP codes of addresses inside each census block, so a ZCTA can differ slightly from the USPS delivery route of the same number, and PO-box-only ZIPs have no ZCTA at all.
Keep going
Related pages for this area.
Sources & transparency
- US Census Bureau, ACS 2019-2023 5-year estimates — 2019-2023 ACS 5-year — population, income, housing
- Census 2020 ZCTA-to-county relationship file — County assignment by largest land-area overlap
- Comptroller of Maryland — Sales tax rates and local add-ons
Last reviewed December 2024. Figures are published for reference and can change; verify with the source agency before filing or contracting. How we build and check this data.