Connecticut: what the state takes
Connecticut charges its own income tax on top of federal tax. Here is the rate, the return, the date and where the official rules live.
Agency page last read 11 September 2026.
State rate
Banded
2025 Connecticut bands with the personal exemption treated as a deduction. The recapture for high earners is not modelled
Resident return
Form CT-1040
Connecticut Department of Revenue Services
Due
15 April, following the federal deadline
Weekends and holidays can push it on
Try a figure
Yearly income
How you file
Connecticut tax
$2,550
Top state rate you touch
5.5%
- Kept before federal tax$58,598
- Federal income tax$13,852
- Connecticut tax$2,550
Band by band
State deduction taken off first: $15,000. Taxed amount: $60,000.
- $0 to $10,000 at 2%$200
- $10,000 to $50,000 at 4.5%$1,800
- $50,000 to $100,000 at 5.5%$550
Filing in Connecticut
- Who collects it
- Connecticut Department of Revenue Services
- Return
- Form CT-1040
- Deadline
- Usually 15 April, following the federal deadline
Federal comes on top
Whatever your state does, the IRS wants Form 1040 by 15 April, plus Social Security and Medicare through your wages or self employment tax. State tax paid can sometimes be deducted federally if you itemise, within a yearly cap.