Thornton Sales Tax Calculator
The combined sales tax rate in Thornton, Colorado is 8.5% in 2026 — a 2.9% Colorado state rate plus 5.6% in local add-ons. That is the 13th highest rate of the 41 Colorado cities we track, and it runs above Colorado's 7.86% 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 →
Thornton sales tax rate in 2026
Thornton charges a combined sales tax rate of 8.5%: the Colorado statewide base of 2.9% plus 5.6% in city and county add-ons. Thornton is in Adams County. Thornton administers its own sales tax (home-rule); the combined rate shown is published by the Colorado Department of Revenue for information.
That local add-on is set by Thornton and the taxing districts that overlap it, which is why neighboring cities in Colorado can charge a different total even a few miles apart.
Thornton vs the rest of Colorado
At 8.5%, Thornton runs above Colorado's 7.86% statewide average combined rate by 0.64%. Among the 41 Colorado cities we track by combined rate, Thornton ranks the 13th highest.
That puts Thornton on the higher end for Colorado — worth double-checking against the official lookup tool if you're quoting a price to a customer or filing a return.
Sales tax examples in Thornton
At Thornton'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 Thornton 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 Thornton's exact rate
The 8.5% rate applies within Thornton's official city limits as published by Colorado DOR — Sales & Use Tax Rate Lookup (DR 1002). Addresses with a Thornton 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: Colorado DOR — Sales & Use Tax Rate Lookup (DR 1002). This calculator pre-fills the published city-limits rate as a reliable starting point.
Thornton sales tax — frequently asked questions
What is the sales tax rate in Thornton, Colorado?
Thornton's combined sales tax rate is 8.5% in 2026 — 2.9% Colorado state tax plus 5.6% in local add-ons. That's the 13th highest rate of the 41 Colorado cities we track.
How much is sales tax on $100 in Thornton?
At Thornton'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 Thornton?
At Thornton'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 Thornton's sales tax higher or lower than the Colorado average?
Thornton runs above Colorado's 7.86% statewide average by 0.64%, ranking the 13th highest of the 41 Colorado cities we track.
How do I calculate sales tax backwards from a total in Thornton?
Divide the total by 1 plus the rate. A $1,090.00 total in Thornton 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 Thornton's sales tax rate apply everywhere in the Thornton area?
The 8.5% rate applies within Thornton's official city limits. Nearby addresses outside the incorporated boundary can be taxed at a different rate — check Colorado DOR — Sales & Use Tax Rate Lookup (DR 1002) for an address-exact figure.
Compare nearby cities in Colorado
See all 41 Colorado cities ranked by combined sales tax rate, or compare:
Researched & verified by the Calcuris Data & Research Team. How we build and check our tools →