Colorado Self-Employment Tax Calculator (2026)
Federal self-employment tax, federal income tax and Colorado state income tax on 1099 income, plus the quarterly estimated payment to set aside.
- Total tax
- $16,592
- Effective rate
- 23.0%
- Per quarter
- $4,148
- After-tax income
- $55,408
| Breakdown | |
|---|---|
| Net profit (income − expenses) | $72,000 |
| Self-employment tax | $10,173 |
| Social Security (12.4%) | $8,245 |
| Medicare (2.9%) | $1,928 |
| Federal income tax | $4,630 |
| Adjusted gross income | $66,913 |
| Standard deduction | −$16,100 |
| Qualified business income deduction (20%) | −$10,163 |
| Taxable income · marginal rate 12.0% | $40,651 |
| Colorado income tax | $1,789 |
| Total federal + state | $16,592 |
Estimated payments of $4,148 are due Apr 15, 2026, Jun 15, 2026, Sep 15, 2026, Jan 15, 2027.
How the 2026 numbers are calculated
- Net profit is your 1099 income minus deductible business expenses (Schedule C).
- Self-employment tax is 15.3% of 92.35% of net profit: 12.4% Social Security on the first $184,500 of combined wages and net earnings, plus 2.9% Medicare on all of it. An extra 0.9% Medicare tax applies above $200,000 ($250,000 married filing jointly).
- Adjusted gross income is net profit plus any W-2 wages, minus half of the self-employment tax.
- The standard deduction ($16,100 single, $32,200 married filing jointly, $24,150 head of household) and the 20% qualified business income deduction reduce taxable income. The QBI deduction starts phasing out above $201,750 of taxable income ($403,500 joint).
- Federal income tax is applied to what is left using the 2026 brackets for your filing status.
- The child tax credit ($2,200 per child under 17, $500 per other dependent) reduces income tax; up to $1,700 per child is refundable and can offset self-employment tax.
- The earned income credit for filers with children — up to $4,427 with one child, $7,316 with two, $8,231 with three or more — is fully refundable and phases out above $23,890 of income ($31,160 joint).
- Colorado income tax: calculated under the state's own rules, described below.
Colorado and self-employment income
Colorado's flat 4.4% applies to federal taxable income, so the federal standard deduction and the 20% QBI deduction already reduce the state base and the deduction for half of self-employment tax carries over. There are no state exemptions. High earners add back the QBI deduction (above $500,000 of income, $1,000,000 joint) and any federal deduction over $12,000 / $16,000 (above $300,000). The TABOR mechanism can trim the rate in a strong revenue year (4.25% applied to 2024); the Department's forms show 4.4% for both 2025 and 2026.
Colorado rules used by this calculator (2026)
- Colorado applies a flat 4.4% rate for 2026.
- There is no standard deduction.
- Colorado starts from federal taxable income, so the federal standard deduction already applies, adding the federal QBI deduction back only above $500,000 of income ($1,000,000 joint).
- Colorado's earned income credit is 25% of the federal credit, refundable; the calculator applies it.
- A refundable $1,200 falling to $0 by income credit per child under 6; the calculator applies it.
- Colorado starts from federal AGI, so the deductible half of self-employment tax reduces state income as well.
- Colorado has no city or county income tax; Denver, Aurora and a few other cities charge a flat occupational privilege tax of a few dollars a month.
What a Colorado freelancer may still owe
- Colorado requires estimated payments (DR 0104EP) when you expect to owe $1,000 or more.
- There is no city or county income tax; Denver, Aurora and a few other cities charge a flat occupational privilege tax of a few dollars a month. Applied here: the refundable Colorado EITC (50% of the federal credit for 2025, 25% for 2026), the child tax credit per child under 6 ($1,200 to $200 by income) and, for 2025 only, the family affordability credit per child (up to $3,273 under 6 and $2,455 for ages 6–16, phasing out by $85,000 single / $96,000 joint). Sole proprietors who deduct business meals add that deduction back on the Colorado return; the child care credit is not included.
Quarterly estimated tax deadlines (2026)
If you expect to owe $1,000 or more of federal tax for the year, the IRS expects four estimated payments (Form 1040-ES). Colorado runs its own estimated-payment schedule with its own threshold (see above); the calculator's per-quarter figure combines federal and state so you can set aside one amount.
- Federal payment 1: April 15, 2026
- Federal payment 2: June 15, 2026
- Federal payment 3: September 15, 2026
- Federal payment 4: January 15, 2027
The calculator splits your total into four equal payments. To avoid an underpayment penalty you can instead pay 100% of last year's total tax (110% if your prior-year AGI was over $150,000) spread across the four dates.
Common questions
Does Colorado tax self-employment income differently from wages?
For state income tax, net profit from self-employment is ordinary income like wages. The self-employment tax itself is federal only; Colorado does not add a state equivalent.
Is half of self-employment tax really deductible?
Yes, for federal tax. The employer-equivalent half is an adjustment to income on Schedule 1, which lowers your AGI and therefore your federal income tax. It does not reduce the self-employment tax itself.
Does an LLC change these numbers?
A single-member LLC taxed as a sole proprietorship pays exactly what this calculator shows. Electing S-corporation status changes the math (salary plus distributions) and is outside this tool's scope.
What if I moved to Colorado during the year?
Income earned while you were a resident of another state is taxable there under that state's rules. This calculator assumes all income was earned as a Colorado resident.
Data sources and status
Federal figures for 2026: verified · last verified 2026-09-05
- IRS Rev. Proc. 2025-32 (2026 inflation adjustments, incorporating OBBBA changes)
- SSA 2026 COLA fact sheet — Social Security wage base
- 26 U.S.C. §199A as amended by Public Law 119-21 — QBI phase-in range widened to $75,000 / $150,000
- 26 U.S.C. §24 as amended by Public Law 119-21 — CTC $2,200, indexed from 2026
- IRS Form 1040-ES (2026) — estimated tax due dates
- IRS Rev. Proc. 2025-32 §4.06 — earned income credit amounts and §32(i) investment income limit
- IRC §6654(d)(1)(B)–(C), (e)(1) and (f) (required annual payment: lesser of 90% of the current year's tax or 100% of the prior year's, 110% when prior-year AGI exceeds $150,000 / $75,000 MFS; no penalty when the tax less withholding is under $1,000; 'tax' = income tax + SE tax less credits other than withholding), read at law.cornell.edu; Form 1040-ES instructions, 'Who Must Pay Estimated Tax' and the Estimated Tax Worksheet
Colorado figures for 2026: verified · last verified 2026-09-08
- Colorado Department of Revenue — 2026 Form DR 0104EP (estimated tax, rev. 2025-06-10): 'line 2: 4.4% of line 1'; 2026 DR 1098 withholding worksheet (rev. 2025-10-21): 'multiply by 4.40% (0.044)'
- Colorado Legislative Council Staff — June 2026 Economic & Revenue Forecast: TABOR revenue below the cap, 'the income tax rate reduction mechanism will not be triggered in tax years 2026 or 2027'
- H.B. 25B-1001 (2025 special session): the QBI addback under §39-22-104(3)(o) continues indefinitely from 2026; 2025 104 Book for the unchanged mechanics
- C.R.S. §39-22-123.5(2)(d)(II)(C): 25% of the federal credit for 2026 and later, plus a revenue-trigger add-on that the December 2025 OSPB forecast did not trigger — Legislative Council Staff June 2026 forecast ('the expanded EITC will be unavailable for tax year 2026') and the H.B. 26-1289 fiscal note (2026-06-12: 'for tax year 2026, the Colorado EITC is 25 percent'); §39-22-129(4.5): the child tax credit is permanent, thresholds indexed (2026 values not yet published — 2025 carried); no family affordability credit for 2026 (trigger not met; H.B. 26-1223's replacement starts 2027)