How much is self-employment tax in Connecticut?

Self-employment tax has two parts. The federal SE tax is 15.3% — 12.4% Social Security up to the wage base plus 2.9% Medicare — on 92.35% of your net profit. On top of that, Connecticut taxes your net self-employment income through its graduated 2% to 6.99% state income tax brackets.

Does Connecticut have a separate self-employment tax?

No. Connecticut does not levy a distinct self-employment tax. The 15.3% SE tax is entirely federal. Connecticut simply taxes your net self-employment income as ordinary income under the same graduated brackets that apply to wages, with the phasing personal exemption.

What is the 92.35% factor for SE tax?

Self-employment tax is calculated on 'net earnings from self-employment,' which is 92.35% of your net profit. The 7.65% reduction mirrors the employer-side payroll tax a W-2 worker would not pay on, so self-employed people are taxed on a comparable base.

Can I deduct half my self-employment tax in Connecticut?

Yes. The deductible half of your federal SE tax (the employer-equivalent portion) is an above-the-line federal adjustment that lowers your federal AGI, which in turn flows into your Connecticut AGI. This tool subtracts it before applying the Connecticut brackets.

Does this include federal income tax?

No. This calculator covers federal self-employment tax and Connecticut state income tax only. Federal income tax on your business profit is separate and depends on your total income and deductions. Use a federal income-tax or paycheck tool to estimate that line.

Connecticut Self-Employment Tax Calculator

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Self-employed Connecticut residents owe two layers of tax on their profit: the federal self-employment tax that funds Social Security and Medicare, and Connecticut’s state income tax. This calculator computes both from your net Schedule C profit and shows the combined burden.

How it works

Federal SE tax is applied to 92.35% of your net profit:

net earnings   = profit × 0.9235
SE tax         = 12.4% × min(net earnings, wage base) + 2.9% × net earnings
half deduction = SE tax ÷ 2
CT AGI         = profit − half deduction
CT tax         = graduated brackets(CT AGI − phasing exemption)
total          = SE tax + CT tax

The 12.4% Social Security portion stops at the annual wage base, while the 2.9% Medicare portion has no cap. Connecticut then taxes the income through its seven graduated brackets from 2% to 6.99%, after the deductible half of SE tax lowers your adjusted gross income.

Example

On $60,000 of net profit, net earnings are $55,410. SE tax is 15.3% of that, or about $8,478, and half ($4,239) is deductible. Connecticut taxable income is roughly $55,761 after the deduction and exemption phase-out, producing about $2,617 of state tax. The combined total is near $11,095 — an effective rate around 18.5% of profit, before federal income tax.

Notes

This is an estimate covering federal SE tax and Connecticut state income tax. Federal income tax on your profit is separate. High earners may owe the 0.9% Additional Medicare Tax, which this tool does not model. Make quarterly estimated payments to both the IRS and the Connecticut DRS to avoid underpayment penalties; confirm current rates at irs.gov and portal.ct.gov/DRS.