Rock Island Sales Tax Calculator
The combined sales tax rate in Rock Island, Washington is 8.5% in 2026 — a 6.5% Washington state rate plus 2% in local add-ons. That is the 130th lowest rate of the 280 Washington cities we track, and it runs below Washington's 9.47% average. On a $100 purchase that's $8.50 in tax for a $108.50 total.
$100.00 total
Before tax: $100.00 · Sales tax: $0.00 (0%)
State & average combined rates: Tax Foundation 2026. Local rates vary by city/county — adjust the rate for an exact figure. How we calculate →
Rock Island sales tax rate in 2026
Rock Island charges a combined sales tax rate of 8.5%: the Washington statewide base of 6.5% plus 2% in city and county add-ons. Rock Island is in Douglas County.
That local add-on is set by Rock Island and the taxing districts that overlap it, which is why neighboring cities in Washington can charge a different total even a few miles apart.
Rock Island vs the rest of Washington
At 8.5%, Rock Island runs below Washington's 9.47% statewide average combined rate by 0.97%. Among the 280 Washington cities we track by combined rate, Rock Island ranks the 130th lowest.
That makes Rock Island comparatively light on sales tax for Washington, though it's still well above zero.
Sales tax examples in Rock Island
At Rock Island's 8.5% combined rate:
$100 → $8.50 tax, $108.50 total · $1,000 → $85.00 tax, $1,085.00 total · $25,000 car purchase → $2,125 tax, $27,125 total.
Working backwards: a $1,090.00 receipt total in Rock Island means the pre-tax price was $1,004.61 and $85.39 was tax — use “Remove tax” mode above to reverse any total instantly.
A note on Rock Island's exact rate
The 8.5% rate applies within Rock Island's official city limits as published by Washington DOR — Tax Rate Lookup. Addresses with a Rock Island mailing address but outside the incorporated city line — a common situation on the edges of any city — can fall under a different, usually lower, rate.
For an address-exact rate, use the official lookup tool: Washington DOR — Tax Rate Lookup. This calculator pre-fills the published city-limits rate as a reliable starting point.
Rock Island sales tax — frequently asked questions
What is the sales tax rate in Rock Island, Washington?
Rock Island's combined sales tax rate is 8.5% in 2026 — 6.5% Washington state tax plus 2% in local add-ons. That's the 130th lowest rate of the 280 Washington cities we track.
How much is sales tax on $100 in Rock Island?
At Rock Island's 8.5% rate, sales tax on a $100 purchase is $8.50, for a $108.50 total.
How much sales tax will I pay on a $25,000 car in Rock Island?
At Rock Island's 8.5% combined rate, sales tax on a $25,000 vehicle purchase is about $2,125, for a $27,125 total before any trade-in credit or registration fees.
Is Rock Island's sales tax higher or lower than the Washington average?
Rock Island runs below Washington's 9.47% statewide average by 0.97%, ranking the 130th lowest of the 280 Washington cities we track.
How do I calculate sales tax backwards from a total in Rock Island?
Divide the total by 1 plus the rate. A $1,090.00 total in Rock Island works back to a $1,004.61 pre-tax price and $85.39 of tax. Use “Remove tax” mode above to do this automatically.
Does Rock Island's sales tax rate apply everywhere in the Rock Island area?
The 8.5% rate applies within Rock Island's official city limits. Nearby addresses outside the incorporated boundary can be taxed at a different rate — check Washington DOR — Tax Rate Lookup for an address-exact figure.
Compare nearby cities in Washington
See all 280 Washington cities ranked by combined sales tax rate, or compare:
Researched & verified by the Calcuris Data & Research Team. How we build and check our tools →