Connecticut Quarterly Tax Calculator 2026
Rates reviewed · Connecticut Department of Revenue Services
Connecticut has a top income tax rate of 6.99%. Freelancers must make quarterly estimated payments if annual liability exceeds $1,000.
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Tax Information Notice
This content is for informational and educational purposes only. It does not constitute tax, legal, or financial advice. Tax laws change frequently. Always consult a qualified CPA or Enrolled Agent for your specific situation.
Connecticut quarterly tax questions
How much is the quarterly tax for freelancers in Connecticut?
Freelancers in Connecticut pay federal self-employment tax (15.3% of net self-employment income), federal income tax at their bracket, and Connecticut income tax of up to 6.99%. This calculator applies 6.99% as a representative Connecticut rate for freelancer-level income; the top marginal rate is 6.99%.
When are quarterly estimated taxes due in Connecticut for 2026?
Connecticut follows the federal estimated tax schedule for 2026 — Q1: April 15, 2026, Q2: June 16, 2026, Q3: September 15, 2026, Q4: January 15, 2027. The Q3 payment is due September 15, 2026.
Do I have to make Connecticut estimated tax payments?
Connecticut requires estimated payments once you expect to owe $1,000 or more in state income tax for the year. The state form is Form CT-1040ES. Payments can be made online through myconneCT. Filing and paying federal estimated tax does not cover the state amount — they are separate payments.
Where do I pay Connecticut estimated taxes online?
Connecticut accepts online estimated tax payments through myconneCT, run by the Connecticut Department of Revenue Services. Federal payments go through IRS Direct Pay or EFTPS separately.
What happens if I underpay estimated taxes in Connecticut?
The IRS charges an underpayment penalty based on the amount underpaid and the number of days late. Paying at least 90% of this year's tax or 100% of last year's (110% if your AGI exceeded $150,000) meets the federal safe harbour. Connecticut applies its own interest and penalty on late or short state payments.
State payments are administered by the Connecticut Department of Revenue Services via myconneCT.
Tax Information Notice
This content is for informational and educational purposes only. It does not constitute tax, legal, or financial advice. Tax laws change frequently. Always consult a qualified CPA or Enrolled Agent for your specific situation.