Key Tax Facts: Connecticut
- Exempts 75% of Social Security benefits at higher income levels
- Pension and annuity income has a 10%-100% exemption based on income
- Pass-through entity tax (PTET) allows workaround for SALT cap
- No local income taxes beyond the state rate
Connecticut State Income Tax Overview
Connecticut uses a graduated income tax with seven brackets from 2% to 6.99%. Single filers pay 2% on the first $10,000 and reach the top 6.99% rate above $500,000. The two lowest rates were cut for tax year 2024, from 3% to 2% and from 5% to 4.5%, the state's first income tax rate reduction since 1996. Connecticut has no standard deduction but offers a personal exemption of $15,000 for single filers and $24,000 for joint filers, which phases out at higher incomes. The state also provides a property tax credit of up to $300 and a credit for income taxes paid to other states. High earners face a benefit recapture that applies the top rate to all income, not just the amount above the threshold.
Connecticut Income Tax Brackets (Single Filers, 2025)
These are the Connecticut state income tax brackets for single filers. Married-filing-jointly brackets use wider income thresholds. Only the income within each bracket is taxed at that rate -- not your entire income.
| Taxable Income (Single) | Tax Rate |
|---|---|
| $0 - $10,000 | 2% |
| $10,000 - $50,000 | 4.5% |
| $50,000 - $100,000 | 5.5% |
| $100,000 - $200,000 | 6% |
| $200,000 - $250,000 | 6.5% |
| $250,000 - $500,000 | 6.9% |
| Over $500,000 | 6.99% |
Source: Connecticut Department of Revenue Services. Brackets shown are for single filers; married-filing-jointly thresholds are wider.
What a Connecticut Resident Actually Pays: A Worked Example
Your effective tax rate is almost always lower than your top bracket. Here is how the math works for a single filer earning $65,000.
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Frequently Asked Questions -- Connecticut Income Tax
Does Connecticut have a state income tax?
Yes. Connecticut imposes a state income tax with a top marginal rate of 6.99%. This is separate from your federal income tax obligation.
What is the Connecticut income tax rate for 2025?
Connecticut uses a graduated income tax system with rates from 2% to 6.99%. Only the income within each bracket is taxed at that bracket's rate -- not your entire income.
Do I have to file a Connecticut state tax return?
Most full-year Connecticut residents with income above the state filing threshold must file a state return. Check the Connecticut Department of Revenue Services for current thresholds and requirements.
How accurate is this estimate?
This is a planning estimate of your federal income tax only. It does not calculate Connecticut state tax, and it does not account for state deductions, credits, exemptions, or local taxes. Use the Connecticut rate schedule above as a reference, and verify with official Connecticut tax forms or a qualified tax professional.
Does this calculator include federal income tax?
Yes. The calculator estimates your 2025 federal income tax using the official IRS 2025 brackets. It does not compute your Connecticut state tax -- see the Connecticut rate schedule below to work that out.
Where can I find official Connecticut tax forms?
Official forms, instructions, and filing guidance are available at the Connecticut Department of Revenue Services.
What is the sales tax rate in Connecticut?
Connecticut's combined state and average local sales tax rate is 6.35%. This is separate from income tax and applies to most retail purchases -- use our sales tax calculator to check a specific purchase.
When are Connecticut 2025 state taxes due?
2025 taxes are generally filed in 2026. The Connecticut filing deadline is April 15, 2026, the same as the federal deadline.
Understanding Your Connecticut Tax Estimate
Your results combine two separate bills: federal tax owed to the IRS, and Connecticut state tax owed to the Connecticut Department of Revenue Services. The state return is filed separately from your federal Form 1040, with a state filing deadline of April 15. For the mechanics of how bracket math actually works -- why your effective rate is almost always lower than your top bracket -- see our marginal vs. effective tax rate guide.
Lowering Your Connecticut Bill
Pre-tax retirement contributions reduce your federal and Connecticut taxable income in the same move -- see our 401(k) contribution limits and HSA limits guides for the current caps. Beyond that, Connecticut-specific credits and deductions that don't exist at the federal level are listed at the Connecticut Department of Revenue Services -- worth checking, since these are easy to miss if you only look at federal guidance.
Combined Sales + Income Tax Picture
Connecticut's combined state-plus-average-local sales tax rate is 6.35%. If you're self-employed, that's an added layer on top of income tax -- our self-employment tax calculator covers the SE-specific piece separately.
Disclaimer: Estimates for educational purposes only. State tax results are approximations based on published bracket data and do not account for all deductions, credits, exemptions, local taxes, or individual situations. Not tax, legal, or financial advice. Consult the Connecticut Department of Revenue Services or a qualified tax professional for guidance specific to your situation.