Bonus Tax in Connecticut (2026)

A bonus is supplemental pay, and it is usually withheld at a flat federal rate rather than your normal bracket. Employers apply 22% to supplemental wages up to a yearly threshold, and a higher rate on the part above it. FICA comes out on top, and then the Connecticut state layer applies.

Some states have no separate bonus withholding rate. In Connecticut, the aggregate method applies instead, combining the bonus with your regular wages and withholding as if it were one larger paycheck. No flat supplemental rate - Connecticut withholds bonuses under the employee's Form CT-W4 withholding code using the regular (aggregate) method

The employee-funded CT Paid Leave premium still comes out of a bonus, up to the yearly wage cap.

Worked example: a $5,000 bonus in Connecticut

Federal withholding (22%)	$1,100
FICA (Social Security + Medicare)	$383
Connecticut withholding	aggregate method — varies

Assumes year-to-date wages under the $184,500 Social Security wage base. Withholding, not final tax — it reconciles on your return.

Bonus tax calculator (2026)

Bonus amount

State

Federal withholding (flat 22%)	$1,100
FICA (Social Security + Medicare)	$383
Connecticut withholding	aggregate method — varies

Connecticut has no flat supplemental rate — employers combine the bonus with regular wages (aggregate method), so the exact withholding depends on your paycheck. Assumes your year-to-date wages are under the $184,500 Social Security wage base. Withholding, not your final tax — it reconciles on your return.

See what your regular paycheck keeps in Connecticut: Connecticut paycheck calculator.

Frequently asked questions

Why is my bonus taxed so high?

What you see is withholding, not your final tax. Federal rules withhold supplemental pay like a bonus at a flat 22%, which is often more than your normal rate, so the bonus looks heavily taxed. It squares up when you file, where your real rate is applied to your total income.

Does Connecticut have a flat bonus withholding rate?

It depends on the state. The breakdown above shows Connecticut's supplemental rate if it has one, or notes when the aggregate method applies instead.

Federal: IRS 2026 brackets (Rev. Proc. 2025-32) · FICA: IRS Topic 751 · Wage base: SSA · Connecticut: Connecticut DRS / CT General Assembly OLR · CT Paid Leave (employee): CT Paid Leave Authority. Rates current as of July 16, 2026. Annual-liability estimates, not payroll withholding — see methodology.