Castle Rock Sales Tax Calculator
The combined sales tax rate in Castle Rock, Colorado is 8.1% in 2026 — a 2.9% Colorado state rate plus 5.2% in local add-ons. That is the 20th highest rate of the 41 Colorado cities we track, and it runs above Colorado's 7.86% average. On a $100 purchase that's $8.10 in tax for a $108.10 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 →
Castle Rock sales tax rate in 2026
Castle Rock charges a combined sales tax rate of 8.1%: the Colorado statewide base of 2.9% plus 5.2% in city and county add-ons. Castle Rock is in Douglas County. Castle Rock 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 Castle Rock and the taxing districts that overlap it, which is why neighboring cities in Colorado can charge a different total even a few miles apart.
Castle Rock vs the rest of Colorado
At 8.1%, Castle Rock runs above Colorado's 7.86% statewide average combined rate by 0.24%. Among the 41 Colorado cities we track by combined rate, Castle Rock ranks the 20th highest.
That puts Castle Rock 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 Castle Rock
At Castle Rock's 8.1% combined rate:
$100 → $8.10 tax, $108.10 total · $1,000 → $81.00 tax, $1,081.00 total · $25,000 car purchase → $2,025 tax, $27,025 total.
Working backwards: a $1,080.00 receipt total in Castle Rock means the pre-tax price was $999.07 and $80.93 was tax — use “Remove tax” mode above to reverse any total instantly.
A note on Castle Rock's exact rate
The 8.1% rate applies within Castle Rock's official city limits as published by Colorado DOR — Sales & Use Tax Rate Lookup (DR 1002). Addresses with a Castle Rock 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.
Castle Rock sales tax — frequently asked questions
What is the sales tax rate in Castle Rock, Colorado?
Castle Rock's combined sales tax rate is 8.1% in 2026 — 2.9% Colorado state tax plus 5.2% in local add-ons. That's the 20th highest rate of the 41 Colorado cities we track.
How much is sales tax on $100 in Castle Rock?
At Castle Rock's 8.1% rate, sales tax on a $100 purchase is $8.10, for a $108.10 total.
How much sales tax will I pay on a $25,000 car in Castle Rock?
At Castle Rock's 8.1% combined rate, sales tax on a $25,000 vehicle purchase is about $2,025, for a $27,025 total before any trade-in credit or registration fees.
Is Castle Rock's sales tax higher or lower than the Colorado average?
Castle Rock runs above Colorado's 7.86% statewide average by 0.24%, ranking the 20th highest of the 41 Colorado cities we track.
How do I calculate sales tax backwards from a total in Castle Rock?
Divide the total by 1 plus the rate. A $1,080.00 total in Castle Rock works back to a $999.07 pre-tax price and $80.93 of tax. Use “Remove tax” mode above to do this automatically.
Does Castle Rock's sales tax rate apply everywhere in the Castle Rock area?
The 8.1% rate applies within Castle Rock'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:
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