Quarterly Estimated Tax Calculator — Colorado (2026)
If you earn income in Colorado without withholding — freelancing, contracting, rentals, dividends — the IRS expects payment four times a year, not once. This calculator turns your expected 2026 net profit into a per-quarter number covering self-employment tax, federal income tax and Colorado state tax. Colorado uses a flat personal income tax of 4.40% applied to taxable income after a state standard deduction of $16,100.
Colorado Quarterly Tax Calculator
Gross 1099 income minus business expenses.
2026 due dates and safe harbor
Federal estimated payments are due April 15, June 15, September 15 of 2026 and January 15 of 2027. You avoid penalties by paying either 90% of the current year's liability or 100% of last year's (110% if prior-year AGI exceeded $150,000) — the safe-harbor rule.
Colorado runs its own estimated-payment schedule that usually mirrors the federal dates. On $90,000 of net profit the Colorado portion alone is about $743 per quarter.
Underpayment penalties
The IRS charges interest-style penalties per quarter you fall short, currently around 7–8% annualized. Paying late in the year does not fix an early-quarter shortfall unless you use the annualized income method on Form 2210.
Irregular income is common in tech work around Denver: if Q1 is slow and Q4 is huge, the annualized method usually beats four equal payments.
Paying as a Colorado taxpayer
Pay federally through IRS Direct Pay or EFTPS, and Colorado through the state revenue department's online portal — keep confirmation numbers for both.
Several Colorado cities (Denver, Aurora, Greenwood Village, Sheridan, Glendale) charge a flat Occupational Privilege Tax of a few dollars per month.
Local and payroll taxes Colorado adds on top
FAMLI paid-leave premiums take roughly 0.45% of wages from the employee side. That deduction sits outside the federal and state income tax lines, so build it into your own budget on top of the numbers above.
Several Colorado cities (Denver, Aurora, Greenwood Village, Sheridan, Glendale) charge a flat Occupational Privilege Tax of a few dollars per month.
Nobody withholds these for you when you are self-employed in Colorado. Local wage taxes, city business licences and gross-receipts style levies are yours to register for and remit alongside your quarterly federal and state estimates.
Working across a state line from Colorado
Colorado has no income-tax reciprocity agreements, so if you live here and work across a state line you generally file a nonresident return in the work state and claim a credit at home to avoid double taxation.
Remote and hybrid work complicates this further: most states tax income where the work is physically performed, so a Denver resident spending part of the year at a client site in Wyoming may owe a nonresident return there. Keep a day-count log if you split time between states.
The rest of your Colorado tax bill
Colorado charges a 2.9% state sales tax, homeowners pay an average effective property tax of 0.49% of market value, and the minimum wage in force during 2026 is $15.16 an hour.
Home-rule cities add a lot: Denver's combined rate is about 8.81%.
Income tax is only one part of a state's take. Colorado recovers revenue through sales and property tax as well, which is why headline income tax rates alone are a poor guide to how far a salary really goes. Colorado allows a large pension/annuity subtraction ($24,000 at 65+) and fully exempts Social Security for filers 65 and older.
Colorado vs Wyoming on the same salary
On a $90,000 salary, a single filer keeps about $68,893 a year in Colorado against roughly $72,145 in Wyoming — a difference of $3,252, or $271 a month.
Effective combined rates are 23.5% in Colorado and 19.8% in Wyoming. Set that gap against living costs: index 105 here versus 96 there, with property tax at 0.49% and 0.61% respectively.
Colorado income tax brackets 2026 (single filer)
| Taxable income | Rate |
|---|---|
| $0 and up | 4.40% |