What is the property tax rate in Benton County?

The combined effective property tax rate in Benton County, Washington is approximately 1.00%.

Benton County Property Tax Calculator (2026) — Washington Property Tax Almanac

Property Tax in Benton County, 2026

A calculator and field guide for Kennewick-area homeowners — and for anyone considering a move to Benton County — including Washington's 100% assessment ratio, the regular vs. excess levy structure, Initiative 747's 1% annual cap on regular levy revenue growth, and the income-tested Senior Citizens and Disabled Persons Property Tax Exemption with assessed-value freeze.

Benton County, home to Prosser and 213k Washingtonians, operates under Washington State's distinctive levy-based property tax system. Washington uses 100% assessment ratio (assessed at true and fair market value) and total tax combines state school + local school + county + city + special districts (typically expressed as dollars per $1,000 of AV). Initiative 747 (passed by voters in 2001) caps regular levy revenue growth at 1% per year per district.

How the bill is built

Washington's property tax calculation has two main steps. Step 1: Assessed Value. The Benton County Assessor reassesses property annually at true and fair market value. Step 2: Apply combined rate. Total rate combines all overlapping districts (state school + local schools + county + city + EMS + library + fire + park + flood control + cemetery, depending on location). Benton's combined rate is approximately 10.00 per $1,000 of AV. Tax = (AV × combined rate) / 1,000. Benton's effective rate of 1.00% reflects this calculation.

Initiative 747's 1% revenue cap creates structural rate stability. When property values rise, the rate decreases automatically so total levy revenue grows by no more than 1% per year per district (excluding new construction and voter-approved excess levies). This has produced unusually stable effective rates over time — long-term WA homeowners typically see modest, predictable bill growth even during housing bubbles. The cap excludes voter-approved school maintenance and operations levies, which is why school district rates often dominate the combined bill.

Washington has no state income tax — but compensates with high sales tax. Washington is one of nine US states with no state income tax (alongside TX, FL, TN, NV, SD, WY, AK, NH). The state-level sales tax is 6.5%, with local add-ons typically bringing combined sales tax to 8.5-10.5% depending on the locality (King County combined: ~10.1%, among the highest in the United States). For high-income residents the no-income-tax structure typically offsets the high sales tax substantially; for lower-income residents the trade-off is less favorable.

Senior Citizens and Disabled Persons Property Tax Exemption is income-tested. Income limits (2026): under $30,000 = full exemption from regular levies + AV freeze; $30K-$35K = 65% reduction + freeze; $35K-$45K = 35% reduction + freeze. Apply with the Benton Assessor office. The same program applies to disabled veterans — Washington does NOT have a separate veteran-specific full exemption, which puts WA among the less-generous states for disabled veterans relative to TX, FL, MI, NJ, PA, OH, or VA.

2026 Benton County rate breakdown (dollars per $1,000 of AV (100% assessment ratio), Prosser district)

Taxing entity	Rate
Kennewick Public Schools (~$3.05 / $1,000 AV)	3.0500
State School + Local Schools Levies	2.9500
Benton County General + Roads + Misc	1.5000
City of Kennewick + EMS + Library	2.5000
Combined total	10.0000

As of April 26, 2026 · From Benton County Assessor.

Note: Benton County, anchored by Kennewick and Richland (two of the three "Tri-Cities" — the third being Pasco in adjacent Franklin County), is the home of the **Hanford Nuclear Reservation** — the most-significant Manhattan Project site in the United States. The Hanford Engineer Works produced the plutonium for the world's first nuclear bomb (the Trinity test, July 1945) and the Fat Man bomb dropped on Nagasaki (August 1945). The site continues today as the Hanford Site cleanup operation, the largest environmental cleanup project in the United States.

Note: Benton County effective property tax rates run approximately 1.00% — moderate by Washington standards. Washington 100% assessment ratio applies. The Hanford Site cleanup employs ~10,000+ federal contractors and is the dominant economic engine of the Tri-Cities. Pacific Northwest National Laboratory (PNNL, in Richland) is one of the most-prominent US Department of Energy national laboratories, conducting research on environmental remediation, nuclear non-proliferation, and energy systems.

Note: For relocation buyers: Benton County offers **the eastern Washington engineering and government employment choice** — substantial federal/contractor employment at Hanford and PNNL, full Washington benefits (no state income tax), and very affordable home prices ($379K median). The Tri-Cities is one of the fastest-growing metros in eastern Washington since 2010, driven by Hanford employment and the substantial Columbia Basin wine country (the Tri-Cities are at the heart of the Columbia Valley AVA, the largest wine-growing region in Washington).

Senior/disabled exemption and excess levies for 2026

Washington's homeowner tax relief is concentrated in a single income-tested Senior Citizens and Disabled Persons Property Tax Exemption (covering both seniors AND disabled veterans). Initiative 747's 1% revenue cap creates structural rate stability for ALL property owners regardless of exemption status.

Senior Citizens and Disabled Persons Property Tax Exemption

Washington's exemption combines a partial reduction of regular property taxes with a freeze on assessed value at the time of qualification. Income limits (2026) are tiered:

Income under $30,000: Full exemption from regular levies + AV freeze
Income $30,000-$35,000: 65% reduction in regular levies + AV freeze
Income $35,000-$45,000: 35% reduction in regular levies + AV freeze

Eligibility: must be 61+ OR disabled OR a disabled veteran with 80%+ service-connected disability. Apply with the Benton Assessor office. Once qualified, the AV freeze locks in your assessed value as of the qualification year — even if market values rise substantially, your assessed value (and tax base) remains constant. The exemption applies to regular levies only; voter-approved excess levies (typically school M&O) are still owed.

Property Tax Deferral Program (seniors 60+)

Washington offers a Property Tax Deferral Program separate from the senior exemption — eligible seniors 60+ with income under ~$57K can defer property tax payments (with state-paid interest) until the property is sold or transferred. The deferred amount becomes a lien on the property. This is particularly valuable for cash-poor / asset-rich seniors who want to remain in their homes.

Excess Levies (school M&O)

Washington's regular levies are capped at 1% annual revenue growth per district under Initiative 747 (2001). However, voter-approved excess levies — primarily school maintenance and operations levies — are exempt from the 1% cap. Excess levies typically run 2-4 year terms and require 60% voter approval. School excess levies often dominate the combined tax bill (typically 30-50% of the total) — when these levies expire and are renewed (or fail), bills can change significantly. Watch for ballot measures.

Appealing your assessment

Washington's appeal process runs through the County Board of Equalization (BOE). Homeowners file a Petition for Review with the BOE within 60 days of the change of value notice (or by July 1, whichever is later). The BOE holds hearings — homeowners can present comparable sales, recent appraisals, or independent appraiser testimony. BOE decisions can be appealed to the Washington State Board of Tax Appeals within 30 days; from there to Superior Court. Most Washington counties reassess annually under the State Department of Revenue's revaluation cycle.

Cities and towns in Benton County

Benton County contains 6 incorporated municipalities, ranging from Prosser to the smallest village. Search volume for property tax is often city-specific, so here is the complete list — with population from the 2020 US Census, rounded to the nearest 100.

Data: US Census Bureau, 2020 Decennial Census. Populations rounded. Cities marked as "split" straddle a county border — the portion inside Benton County is subject to Benton County's tax rolls, while the portion outside is subject to the adjacent county's.

City or town	Type	Population (2020)
Kennewick	city	84,347
Richland	city	60,560
West Richland	city	16,242
Prosser County seat	city	6,276
Finley	unincorporated	6,005
Benton City	city	3,486

About city-level property tax rates: The rate breakdown and calculator on this page reflect the Prosser tax district. Other cities in Benton County may pay into different school districts, city rates, and special districts — so their combined rates can differ, sometimes substantially. Always verify the specific rates for your address with the Benton County Assessor before relying on any estimate.

Frequently asked questions

When are Washington property taxes due?

Washington property taxes are due in two installments: April 30 (first half) and October 31 (second half). Bills under $50 must be paid in full by April 30. Late payments incur 1% per month interest plus a 3% delinquency penalty after May 31 (first half) or December 1 (second half). Most Washington homeowners pay through escrow via their mortgage servicer. The Benton Assessor office handles collection.

What is Initiative 747 and how does it limit my taxes?

Initiative 747 (passed by Washington voters in 2001) caps regular levy revenue growth at 1% per year per district. When property values rise (sometimes substantially), the rate decreases automatically so total revenue grows by no more than 1%. The cap excludes new construction (so growing districts can collect more) and voter-approved excess levies (primarily school maintenance and operations levies, which require 60% voter approval). I-747 has produced unusually stable effective rates over time — long-term Washington homeowners typically see modest, predictable bill growth even during housing bubbles. The Washington Supreme Court initially struck down I-747 in 2007, but the legislature re-enacted it in a 2007 special session.

How does Washington's no-state-income-tax structure affect total tax burden?

Washington is one of nine US states with no state income tax (alongside TX, FL, TN, NV, SD, WY, AK, NH). The state-level sales tax is 6.5%, with local add-ons typically bringing combined sales tax to 8.5-10.5% depending on locality. For high-income residents, the no-income-tax structure typically produces meaningful net savings — especially for buyers relocating from California (which has top marginal income tax of 13.3%) or New York (10.9%). For lower-income residents, the high sales tax shifts more burden to consumption-based taxation. Property tax effective rates in Washington (~0.8-1.1%) are moderate by national standards.

How do I apply for the Senior/Disabled Persons Exemption?

The Senior Citizens and Disabled Persons Property Tax Exemption is income-tested with three tiers (2026): under $30K = full exemption from regular levies + AV freeze; $30K-$35K = 65% reduction + freeze; $35K-$45K = 35% reduction + freeze. Eligibility: must be 61+ OR disabled OR a disabled veteran with 80%+ service-connected disability. Apply with the Benton Assessor office. Once qualified, the AV freeze locks in your assessed value as of the qualification year. The exemption applies to regular levies only; voter-approved excess levies are still owed. Disabled veterans use this same program — Washington does not have a separate veteran-specific full exemption.

How do I appeal my Washington assessment?

File a Petition for Review with your County Board of Equalization (BOE) within 60 days of the change of value notice (or by July 1, whichever is later). The BOE holds hearings — homeowners can present comparable sales, recent appraisals, or independent appraiser testimony. BOE decisions can be appealed to the Washington State Board of Tax Appeals within 30 days; from there to Superior Court. Most Washington counties reassess annually under the State Department of Revenue's revaluation cycle.

About Benton County

Beyond the property tax — a few things you might not know about the place.

Weird fact

Hanford, Benton County is **where most of the plutonium for the United States nuclear weapons program was produced** — approximately 67 metric tons of weapons-grade plutonium (representing the bulk of the US Cold War nuclear arsenal's plutonium content) was produced at Hanford between 1944 and 1989 across nine production reactors. The site's B Reactor (the world's first full-scale plutonium production reactor, operational September 1944) is now a National Historic Landmark and part of the Manhattan Project National Historical Park. Hanford's 56 million gallons of high-level radioactive waste in 177 underground tanks represents the most-contaminated site in the Western Hemisphere.

Hometown hero

Sam Volpentest

The Tri-Cities' most-prominent civic leader (1909-2005) — a businessman and political organizer who is widely credited with single-handedly preventing the closure of the Hanford Site after the Cold War. Volpentest spent decades building bipartisan congressional support for continued Hanford funding, transitioning the site from weapons production to environmental cleanup. The Volpentest HAMMER Federal Training Center at Hanford is named in his honor. Without Volpentest's political organizing, the Tri-Cities would have likely experienced a precipitous economic decline similar to other former Manhattan Project sites.

Biggest annual event

Tri-Cities Water Follies (Columbia Cup) + wine country events

The Tri-Cities Water Follies (annual, late July on the Columbia River) culminates in the Lamb Weston Columbia Cup — a Unlimited Hydroplane Racing event (Tri-Cities is one of the few remaining cities in the United States to host professional unlimited hydroplane racing). The Columbia Valley wine country events (centered in Prosser, Benton County) include the Spring Barrel Tasting (April), the Catch the Crush (October), and dozens of winery-specific events at the 200+ wineries in the Columbia Valley AVA.

Property Tax in Benton County, 2026