Property Taxes in Gaithersburg, Maryland
Median Gaithersburg, Maryland effective property tax rate: 1.18%, significantly higher than the national median of 1.02%, and lower than the Maryland state median of 1.21%.
Median Gaithersburg, Maryland home value: $463,100
Median annual Gaithersburg, Maryland tax bill: $5,434, $3,034 higher than the national median property tax bill of $2,400.
How are property taxes in Montgomery calculated?
Property taxes in Gaithersburg, Maryland are calculated based on the tax assessed value, which is often lower than the actual market value due to property tax exemptions such as the homestead or senior exemption.
Understanding Gaithersburg's property tax system, exemptions, and reduction opportunities can lead to significant savings. Regardless of where you live in Gaithersburg, knowing local tax details benefits homeowners and investors.
Last Updated April 13, 2026
How Does the Gaithersburg Property Tax Calculator Work?
Use this Gaithersburg property tax calculator to estimate your annual property tax bill. Enter your property's assessed value and the calculator applies Gaithersburg's median effective tax rate of 1.18% — based on actual property records in Montgomery County — to generate your estimate.
Enter your property's estimated assessed value — the figure the local assessment process uses to calculate your bill, which reflects any exemptions you hold and is typically lower than your home's market value. The calculator applies Gaithersburg's median effective rate across all local levies, providing a more accurate estimate than using a single county millage rate.
Your bill may vary by ZIP code within Gaithersburg: rates range from $3,714 in 20886 to $7,374 in 20882, primarily due to differences in school district levies and local assessment districts.
Gaithersburg's median tax rate is higher than the 1.02% national median property tax rate and higher than Maryland's 1.21% state median tax rate. For a more precise estimate, scroll down to explore ZIP code-level tax rate trends across Gaithersburg.
About Gaithersburg Property Taxes
About Property Taxes in Gaithersburg, Montgomery, Maryland
Gaithersburg’s median effective property tax rate of 1.18% is lower than the Maryland state median of 1.21% and higher than the national median of 1.02%. This rate reflects the Montgomery County base levy combined with local school district levies and special taxing districts that vary by subdivision throughout the city.
Property tax rates are not uniform across Gaithersburg. Homeowners in the 20878 ZIP code carry a median effective rate of 1.22%, while those in 20879 pay 1.11%. This spread — 0.11 percentage points across the same city — reflects how school district boundaries and local assessment districts are drawn across Montgomery County. Understanding which part of Gaithersburg you live in can make a meaningful difference to your annual tax bill.
Gaithersburg homeowners who believe their assessed value is too high can file a formal appeal with the local Tax Assessor before the February 13, 2026 deadline each year.
If your estimated bill above seems higher than expected, Ownwell can review your assessment and protest on your behalf. You only pay if we save you money.
Property Tax Rates Across Gaithersburg, Montgomery County, Maryland
As noted earlier, local government entities set tax rates, which can vary widely within a state.
Why? Because annually, each county estimates its required budget to provide services and divides that by the total value of all taxable property within its jurisdiction. This calculation results in the property tax rate.
While there are votes and laws involved in setting tax rates and budgets, in a nutshell, this is the annual process.
Below, you can compare Gaithersburg's effective property tax rate to other cities in Maryland and the median property tax rates in Maryland and the U.S.
Our median effective property tax rate (tax bill ÷ assessor's market value) accounts for exemptions and deductions, making it more accurate than the general median tax rate, which is the midpoint of statutory rates before adjustments.
Median Effective Gaithersburg Tax Rate
1.18%
Our median effective property tax rate (tax bill ÷ assessor's market value) accounts for exemptions and deductions, making it more accurate than the general median tax rate, which is the midpoint of statutory rates before adjustments.
Median Effective Montgomery County Tax Rate
1.19%
Median Effective Maryland Tax Rate
1.21%
Median Effective United States Tax Rate
1.27%
Property Tax Rates Across Gaithersburg, Montgomery County, Maryland
| Zip | 10th Percentile | 25th Percentile | Median Tax Rate | 75th Percentile | 90th Percentile |
|---|---|---|---|---|---|
| 20877 | 1.07% | 1.10% | 1.16% | 1.21% | 1.25% |
| 20878 | 1.12% | 1.18% | 1.22% | 1.25% | 1.27% |
| 20879 | 0.97% | 1.05% | 1.11% | 1.15% | 1.20% |
| 20882 | 1.00% | 1.06% | 1.19% | 1.26% | 1.29% |
| 20886 | 1.08% | 1.10% | 1.11% | 1.12% | 1.14% |
Source: Ownwell
Property Tax Assessment Values Across Gaithersburg, Montgomery County, Maryland
When examining property taxes in Gaithersburg, Maryland, understanding the distinction between "market value" and "assessed value" is crucial.
The market value is what a willing buyer would pay to a willing seller in an open and competitive market, often influenced by location, property condition, and economic market trends. The Montgomery County tax assessor estimates the market value for tax purposes.
The assessed value is the market value minus any applicable exemptions or limits determined by local laws and offerings. The tax assessed value is the figure used to calculate your property taxes or the amount multiplied by your tax rate to get your tax bill.
Assessment notices:
In Montgomery County, assessment notices are sent in the spring each year. They'll typically reach your mailbox by the middle of the month when notices are sent.
Each property owner receives an assessment notice that contains both the market value and assessed value, along with an estimate of your property tax bill. By providing insights into how assessed and market values are determined, this section helps property owners navigate their tax responsibilities and understand the valuation processes affecting their property taxes in Gaithersburg.
For example, the median home price in Gaithersburg is $463,100, with tax bills ranging significantly across the county. 20882 has the highest median home price at $642,250.
Property Tax Assessment Values Across Gaithersburg, Montgomery County, Maryland
Source: Ownwell
$110,000
$614,075
$1,118,150
Median Gaithersburg Market Value
$463,100
Median Montgomery County Market Value
$520,100
Median Maryland Market Value
$338,400
Median United States Market Value
$274,101
Property Tax Assessment Values Across Gaithersburg, Montgomery County, Maryland
| Zip | 10th Percentile | 25th Percentile | Median Home Price | 75th Percentile | 90th Percentile |
|---|---|---|---|---|---|
| 20877 | $170,000 | $335,000 | $411,200 | $518,100 | $588,640 |
| 20878 | $315,000 | $386,250 | $535,000 | $712,300 | $931,400 |
| 20879 | $215,000 | $315,700 | $376,300 | $484,050 | $618,000 |
| 20882 | $367,510 | $465,175 | $642,250 | $839,400 | $1,014,660 |
| 20886 | $304,990 | $318,225 | $330,000 | $346,925 | $366,420 |
Source: Ownwell
Property Tax Bills Across Gaithersburg, Montgomery County, Maryland
Gaithersburg property tax bills are calculated by applying the local tax rate to a home’s assessed value, which is based on the market value of the property. For homeowners, the bill depends on both the value of the home and the rate set for the area, so two similar homes can still have different tax bills if their assessed values differ.
In Gaithersburg, the median home price is $463,100, and property tax bills vary widely across the city. The 25th percentile tax bill is $4,139, while the 75th percentile reaches $7,661. At the high end, the 90th percentile tax bill is $9,784. By ZIP code, the highest median tax bill is $7,374 in 20882, and the lowest median tax bill is $3,714 in 20886.
Because property taxes are tied to assessed value, rising home values can increase a homeowner’s bill even if nothing changes about the property itself.
Property Tax Bills Across Gaithersburg, Montgomery County, Maryland
Source: Ownwell
$1,261
$7,418
$13,575
Median Gaithersburg Tax Bill
$5,434
Median Montgomery County Tax Bill
$6,208
Median Maryland Tax Bill
$4,092
Median United States Tax Bill
$3,209
Property Tax Bills Across Gaithersburg, Montgomery County, Maryland
| Zip | 10th Percentile | 25th Percentile | Median Tax Bill | 75th Percentile | 90th Percentile |
|---|---|---|---|---|---|
| 20877 | $1,837 | $3,821 | $4,762 | $6,013 | $6,795 |
| 20878 | $3,481 | $4,725 | $6,464 | $8,733 | $11,353 |
| 20879 | $2,015 | $3,573 | $4,360 | $5,305 | $6,520 |
| 20882 | $4,469 | $5,664 | $7,374 | $9,109 | $10,891 |
| 20886 | $3,446 | $3,562 | $3,714 | $3,809 | $3,962 |
Source: Ownwell
Don't miss the deadline to appeal!
Dates | |
|---|---|
| Appeal Deadline | February 13 |
Links | |
|---|---|
| Montgomery Tax Assessor | |
| Website | sdat.dat.maryland.gov |