1099 tax in California stacks three layers on the same income: federal self-employment tax at 15.3%, federal income tax between 10% and 37%, and California state income tax between 1% and 13.3%. Most freelancers keep somewhere between 60 and 75 cents of every dollar earned. Where you land in that range depends on how much you net, your filing status, and the deductions you claim.
The Three Layers on Your 1099 Income
Federal Self-Employment Tax (15.3%)
Self-employment tax is the piece that surprises most new freelancers. Employees split Social Security and Medicare with their employer. When you work for yourself, you pay both halves: 12.4% for Social Security and 2.9% for Medicare, for a combined 15.3% on net self-employment earnings.1Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes)
The 15.3% doesn’t apply to your entire net. You first multiply net earnings by 92.35%, which mimics the break employees get when their employer’s share isn’t counted as wages. On $100,000 of net self-employment income, the tax applies to $92,350.
The 12.4% Social Security portion only applies up to $184,500 in combined wages and self-employment income for 2026.2Social Security Administration. Contribution and Benefit Base The 2.9% Medicare piece has no cap. And you get to deduct half your self-employment tax when calculating adjusted gross income, which lowers what’s subject to both federal and state income tax.1Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes)
If your net self-employment income exceeds $200,000 single or $250,000 married filing jointly, an extra 0.9% Additional Medicare Tax kicks in on the amount above those thresholds, bringing the Medicare rate to 3.8% on that top slice.3Office of the Law Revision Counsel. 26 USC 1401 – Rate of Tax Given California’s concentration of well-paid contractors, this hits more 1099 workers here than in most states. It’s reported on Form 8959.4Internal Revenue Service. Questions and Answers for the Additional Medicare Tax
Federal Income Tax (10% to 37%)
Your net business profit flows through to your personal return and is taxed at the same progressive rates as wages. For 2026, single filers pay:5Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026, Including Amendments From the One, Big, Beautiful Bill
- 10% up to $12,400
- 12% from $12,401 to $50,400
- 22% from $50,401 to $105,700
- 24% from $105,701 to $201,775
- 32% from $201,776 to $256,225
- 35% from $256,226 to $640,600
- 37% above $640,600
Married joint filers get wider brackets. The 10% band runs to $24,800, the 12% band to $100,800, and 37% doesn’t hit until income above $768,700.5Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026, Including Amendments From the One, Big, Beautiful Bill
Before applying brackets, you reduce income by the standard deduction: $16,100 single, $32,200 married joint, $24,150 head of household for 2026.5Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026, Including Amendments From the One, Big, Beautiful Bill
California State Income Tax (1% to 13.3%)
California layers its own progressive tax on top. Nine brackets run from 1% to 12.3%, applied to net self-employment profit after the half-SE-tax deduction and any California-allowable business expenses.6Franchise Tax Board. 2024 California Tax Rate Schedules The Franchise Tax Board handles collection.7Franchise Tax Board. Self-Employed
Cross $1 million in taxable income and an additional 1% surcharge applies to every dollar above that line. That’s the Behavioral Health Services Tax, and it pushes the effective top rate to 13.3%, the highest state income tax in the country.8California Legislative Information. California Code RTC 17043 – Imposition of Tax
A $100,000 Example
Take a single freelance web developer in Los Angeles netting $100,000 in 2026 with no other income:
- Self-employment tax: 15.3% on $92,350 = about $14,130
- Half-SE-tax deduction: $7,065 reduces AGI to about $92,935
- Federal QBI deduction: 20% of $92,350 = about $18,470
- Federal standard deduction: $16,100
- Federal taxable income: about $58,365, producing roughly $7,500 in federal income tax
- California taxable income: about $87,395 (no QBI deduction, smaller state standard deduction), producing roughly $3,500 to $4,000 in state tax
Total tax: about $25,000 on $100,000 of net income, or a 25% effective combined rate.
How the Math Shifts at Higher Incomes
At $250,000 in net income you’d hit the Additional Medicare Tax, land in higher federal brackets, and pay California at rates near 9%. The combined effective rate climbs into the 35–40% range. Above $1 million, the 1% surcharge tacks on to state tax.
One structural note worth pinning down: the federal Section 199A qualified business income deduction lets eligible self-employed people deduct up to 20% of qualified business income before federal income tax is calculated.9Office of the Law Revision Counsel. 26 USC 199A – Qualified Business Income Below $201,750 single or $403,500 joint in taxable income, you generally get the full 20% without restrictions. Above those thresholds the deduction phases out, and service businesses like consulting, law, accounting, and financial advising face stricter limits, with the deduction disappearing entirely above $276,750 single or $553,500 joint.
California doesn’t conform to Section 199A. You take the 20% on your federal return; it does nothing for your California bill. That’s part of why California’s effective rate on 1099 income runs higher than in most states.
Deductions That Lower the Bill
Every dollar of legitimate business expense reduces income for both self-employment tax and income tax. That double benefit means a $1,000 deduction can be worth $350 or more, depending on your bracket.
Home Office
If you use part of your home regularly and exclusively for business, you can deduct a portion of housing costs. The simplified method is $5 per square foot up to 300 square feet, capped at $1,500 a year.10Internal Revenue Service. Simplified Option for Home Office Deduction The regular method tracks actual rent, utilities, and insurance proportional to office space, which often produces a larger deduction in high-cost California markets but takes more recordkeeping.
Health Insurance Premiums
Self-employed people can deduct 100% of health insurance premiums paid for themselves, a spouse, and dependents, provided they aren’t eligible for a subsidized plan through a spouse or other source.11Internal Revenue Service. Instructions for Form 7206 – Self-Employed Health Insurance Deduction With California premiums running well above the national average, this alone can be worth thousands. The policy has to be established under your business, and it’s reported on Form 7206.
Mileage and Other Common Write-Offs
The 2026 IRS standard mileage rate for business driving is 72.5 cents per mile. Ten thousand business miles is $7,250 off taxable income without tracking every gas receipt. Other frequently missed items include software subscriptions, professional development, business insurance, and a dedicated phone line or internet service used for work.
Quarterly Payments: California’s Schedule Differs From Federal
No employer withholds from your 1099 income, so you pay as you earn through quarterly estimated payments. Miss deadlines and you owe interest and penalties on top of the tax.
Federal payments are due April 15, June 15, September 15, and January 15 of the following year, each covering roughly a quarter of expected annual liability.12Internal Revenue Service. Estimated Tax Amounts are figured on Form 1040-ES.13Internal Revenue Service. Form 1040-ES – Estimated Tax for Individuals
California doesn’t follow that pattern. The Franchise Tax Board requires 30% of your estimated annual tax by April 15, 40% by June 15, nothing in September, and 30% by January 15.14State of California Franchise Tax Board. Estimated Tax Payments That means 70% of your California estimated tax is due by mid-June. Freelancers who budget on the federal rhythm regularly come up short on the June state payment. State amounts are figured on Form 540-ES.15Franchise Tax Board. 2025 Instructions for Form 540-ES Estimated Tax for Individuals
Safe Harbor: How to Avoid Underpayment Penalties
The federal underpayment interest rate for 2026 sits around 6–7%, applied quarterly to any shortfall and compounding.16Internal Revenue Service. Quarterly Interest Rates Falling behind early in the year costs more than falling behind at the end.
The IRS won’t penalize you if you meet any of these thresholds:17Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty
- You owe less than $1,000 after subtracting withholding and credits.
- You paid at least 90% of what you end up owing for 2026.
- You paid at least 100% of last year’s total tax. If your prior-year AGI exceeded $150,000 ($75,000 married filing separately), that threshold rises to 110%.
The prior-year method is popular with freelancers whose income fluctuates because it gives a fixed target regardless of how the current year turns out. California follows a similar framework: 90% of current-year state tax or 100% of prior-year state tax, with a minimum threshold of $500 ($250 if married filing separately).14State of California Franchise Tax Board. Estimated Tax Payments