What this calculator does
This calculator estimates the full tax on freelance, gig or 1099 income for someone living in Seattle: self-employment tax for Social Security and Medicare, the extra federal income tax the profit causes, and Washington tax. It also shows a quarterly estimated payment and the share of each dollar to set aside.
Seattle freelancers owe no state income tax, but Washington's business and occupation (B&O) tax can apply to gross receipts above the small-business credit, and Seattle has its own business license tax.
How to use it
- Enter net profit — revenue minus business expenses, the number on Schedule C.
- Add any W-2 wages from a job this year so the tool can figure your bracket and Social Security limit.
- Choose your filing status.
- Add retirement contributions to a SEP-IRA or Solo 401(k), which lower income tax but not self-employment tax.
The formula
Self-employment tax = net profit × 92.35% × (12.4% Social Security up to the $184,500 wage base, minus any W-2 wages, + 2.9% Medicare, + 0.9% Additional Medicare above $200,000 single). Half of the SE tax is deductible. Federal and state income tax on the business is the tax on (wages + profit − half SE tax − retirement) minus the tax on wages alone. Quarterly estimate = total ÷ 4.
Worked example for Seattle
A single freelancer in Seattle with $80,000 of net profit and no other job:
| Item | Amount |
|---|---|
| Net profit (Schedule C) | $80,000 |
| Net earnings for SE tax (x 92.35%) | $73,880 |
| Social Security part (12.4%) | $9,161 |
| Medicare part (2.9% + 0.9% over threshold) | $2,143 |
| Deduction for half of SE tax | -$5,652 |
| Retirement contribution (SEP/Solo 401k) | $0 |
| Total estimated tax on this income | $18,830 |
About $4,708 per quarterly estimated payment · set aside 23.5% of profit.
What affects freelance taxes in Seattle
Washington does not tax wages, so Seattle paychecks show federal income tax and FICA plus two small state premiums. The state does tax long-term capital gains above a standard deduction at 7% (9.9% on taxable gains above $1 million), and it enacted a 9.9% tax on household income over $1 million that is scheduled to start in 2028.
Business expenses are the biggest lever: every legitimate expense lowers both self-employment tax and income tax. Home office, equipment, software, health insurance premiums for the self-employed and part of your phone bill are common deductions. Retirement contributions lower income tax only.
Common mistakes and tips
- Setting aside only your income-tax bracket rate and forgetting the 15.3% self-employment tax.
- Missing quarterly deadlines (usually April 15, June 15, September 15 and January 15), which can bring an underpayment penalty.
- Mixing personal and business money, which makes expenses hard to prove.
- Forgetting the qualified business income deduction, which can lower federal tax for many freelancers (not included in this estimate).
- Overlooking local business taxes and registrations in Seattle — see the note in the results.
Frequently asked questions
How much should I set aside for taxes as a freelancer in Seattle?
With $80,000 of profit and no other income, this estimate suggests about 23.5% of profit of profit. Higher profit, W-2 income or federal brackets push that share up.
What is the self-employment tax rate?
15.3% on 92.35% of net earnings: 12.4% for Social Security up to the wage base ($184,500 in 2026) and 2.9% for Medicare, plus 0.9% Additional Medicare above $200,000 for single filers.
When are quarterly estimated taxes due?
For most people: April 15, June 15, September 15 and January 15 of the following year. States with income tax generally use the same dates.
Does Washington tax freelance income?
No. Washington has no personal income tax, so only federal income tax and self-employment tax apply to the profit.
Is the QBI deduction included?
No. The qualified business income deduction can reduce federal income tax by up to 20% of qualified profit for many freelancers, subject to income limits. Leaving it out keeps the estimate on the cautious side.
Sources
Disclaimer
This calculator provides estimates for educational purposes only and is not financial, tax, legal, real estate, or insurance advice. Consult a licensed professional before making decisions.