Whatcom County, WA Property Tax: $3,819/yr (2026)
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The effective property tax rate in Whatcom County is 0.71% of assessed home value. On a home at the county median value of $536,100, that works out to about $3,806 per year, or $317 per month. Whatcom County is located in northern Washington, and is home to approximately 228,432 residents.
About Whatcom County
Whatcom County covers approximately 2,107.9 square miles in Washington. The county is home to about 228,432 residents living in roughly 101,928 housing units, of which 57.6% are owner-occupied. The median household income is $80,989, and the median home was built in 1988.
Whatcom County borders Okanogan County, San Juan County, Skagit County — useful comparisons if you're considering nearby areas with potentially different tax rates.
How Property Taxes Work in Washington
Property taxes in Washington are administered at the county level. Each county sets a millage rate applied to the assessed value of real property — the effective rate above accounts for any partial assessments and exemptions already built into the local tax base. Assessed value can differ meaningfully from current market value depending on how often the county reassesses and what fraction of market value it uses.
Most counties in Washington offer exemptions that reduce the taxable assessed value: homestead exemptions for primary residences, senior exemptions, disability exemptions, and veteran exemptions are common. These reduce your effective rate below the county-wide average shown here. Contact the Whatcom County Assessor's office to learn which exemptions apply to your property and when to file.
Whatcom County vs. Neighboring Counties
| Location | Eff. Rate | Median Home | Annual Tax |
|---|---|---|---|
| Whatcom County, WA | 0.71% | $536,100 | $3,806 |
| Washington state average | 0.76% | — | $4,074* |
| Okanogan County | 0.77% | $284,200 | $2,194 |
| San Juan County | 0.57% | $726,500 | $4,131 |
| Skagit County | 0.82% | $486,200 | $4,008 |
| US national average | 1.10% | $281,900 | $3,101 |
*State average annual tax computed at Whatcom County's median home value of $536,100. Source: US Census ACS 2023 5-year estimates.
Frequently Asked Questions
How does Whatcom County's property tax rate compare to the rest of Washington?
At 0.71%, Whatcom County is lower than the Washington state average of 0.76%. On a home at the county median of $536,100, that means about $3,806 per year — versus $4,074 at the state average rate, a difference of $268 per year. Compared to the national average of 1.10%, Whatcom County is below average.
What's a typical annual property tax bill in Whatcom County?
For a home at the county median value of $536,100, the annual property tax in Whatcom County is approximately $3,806 — or about $317 per month. For a home worth $804,150, expect around $5,709 per year. For a $1,072,200 home, approximately $7,613 per year. Use the calculator above to estimate taxes for any assessed value.
Where do I appeal a Whatcom County property tax assessment?
Property assessment appeals in Whatcom County are handled by the Whatcom County Assessor's office. Most jurisdictions require filing within 30–90 days of receiving your assessment notice — confirm the specific deadline with the assessor's office before submitting, as deadlines and procedures vary by county. A successful appeal can reduce your assessed value and lower your tax bill for the current and future tax years.
What exemptions are available in Whatcom County?
Washington counties commonly offer homestead exemptions for owner-occupied primary residences, senior citizen exemptions for qualifying homeowners aged 65 and older, exemptions for disabled residents, and veterans' exemptions. Each exemption reduces your assessed taxable value, which in turn reduces your effective tax rate below the county-wide 0.71% shown here. Contact the Whatcom County Assessor's office to confirm which exemptions are available and the application deadlines.
Data sources: US Census Bureau ACS 2023 5-Year Estimates, US Census Gazetteer (2024), County Adjacency File