Connecticut Income Tax Calculator 2026

Connecticut Income Tax: Graduated Brackets Up to 6.99%

Connecticut uses a progressive income tax system with 7 brackets. Rates range from 3.0% to 6.99%, with higher income taxed at higher rates. Connecticut also applies a tax on capital gains and has a personal tax credit for lower-income filers.

Like federal taxes, Connecticut's system is marginal — only the income within each bracket is taxed at that bracket's rate. Combined with federal taxes (10%–37%), Connecticut residents can face a total marginal rate of up to 43.99% on their highest dollars of income.

Connecticut Tax Brackets for 2026 (Single Filer)

The Connecticut income tax brackets for single filers are:

• 3.0% on income from $0 to $10,000
• 5.0% on income from $10,000 to $50,000
• 5.5% on income from $50,000 to $100,000
• 6.0% on income from $100,000 to $200,000
• 6.5% on income from $200,000 to $250,000
• 6.9% on income from $250,000 to $500,000
• 6.99% on income over $500,000

Your marginal rate is the rate on your last dollar of income. Your effective rate (total tax divided by total income) is always lower because of the progressive structure.

Tips to Lower Your Connecticut Tax

Maximize pre-tax retirement contributions to reduce both federal and Connecticut taxable income. The 2026 401(k) limit is $24,500 ($32,500 with catch-up for age 50+). If Connecticut conforms to federal deductions, your standard deduction and itemized expenses also reduce your state tax liability.