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California · SE Tax · Deductions · Quarterly Payments · 2026

Self-Employed Tax Calculator 2026 — California

Self-employed workers in California face one of the highest combined tax burdens in the US — federal SE tax at 15.3% stacks on California's progressive income tax reaching 13.3% plus a 1.1% SDI contribution, pushing total effective rates above 40% for many sole proprietors. Maximizing deductions for home office, vehicle mileage, and SEP-IRA contributions is essential for California self-employed workers.

Also see: California Quarterly Tax Calculator →

Business Income

$

Total revenue before any deductions

$

Equipment, software, office supplies, subscriptions, etc.

Location & Filing

After-Tax Income

$56,011

Total tax burden: $18,989 — 25.3% effective rate

Tax Breakdown

Gross SE Income$75,000
Business Deductions−$5,000
Net SE Income$70,000
SE Tax (15.3%)−$9,891
Federal Income Tax−$5,684
State & Local Tax−$3,414
After-Tax Income$56,011

Your Deductions

Business expenses−$5,000
SE tax deduction (50%)−$4,945
Total deductions−$9,945

Estimated tax savings from deductions: $2,188

2026 Quarterly Estimated Payments

Q1 (Jan–Mar)

$4,747

Due April 15, 2026

Q2 (Apr–May)

$4,747

Due June 16, 2026

Q3 (Jun–Aug)

$4,747

Due September 15, 2026

Q4 (Sep–Dec)

$4,747

Due January 15, 2027

Set aside $1,582/month to be ready for each payment.

💡Marginal tax system: only the income within each bracket is taxed at that rate — not your entire income.
10%$0 – $11,925$1,193

$11,925 taxable in this bracket

12%$11,925 – $48,475$4,386

$36,550 taxable in this bracket

22%$48,475 – $103,350$106← marginal rate

$480 taxable in this bracket

24%$103,350 – $197,300—not reached
32%$197,300 – $250,525—not reached
35%$250,525 – $640,600—not reached
37%$640,600+—not reached
Deduction used$16,100
Taxable income$48,955
Total federal tax$5,684
Effective rate11.6%
Marginal rate22%

Frequently Asked Questions

Do I need to pay both federal and state SE taxes?

Self-employment tax (SE tax) is a federal tax — there is no state-level self-employment tax. However, most states tax your self-employment income as ordinary income under their regular income tax. Nine states have no income tax at all. The total tax burden shown in this calculator includes both federal SE tax and your state's income tax on self-employment income.

Do state deductions work the same as federal?

Many states follow federal treatment for common deductions like business expenses and SE tax deductions, but not all. Some states don't allow the home office deduction, and state retirement contribution limits or health insurance deduction rules may differ from federal. This calculator applies federal deduction rules, which are a good approximation for most states — consult a local tax professional for state-specific deduction limits.