Connecticut: corporate income tax, no franchise tax and an annual report due in your anniversary month.
Each fact below cites the agency page we read and the day we read it. Where a rule is still being confirmed, the page says so instead of showing a zero.
Verified facts
Corporate income tax
Yes
Corporation Business Tax is the greater of the net income base (7.5 percent of apportioned Connecticut net income) or the capital base (0.21 percent of apportioned capital); a 10 percent surtax applies to companies with federal total…
Franchise or privilege
No
Connecticut does not impose a separate franchise or privilege tax. The corporate-level tax is the Corporation Business Tax, computed on the greater of a net income base or a capital base, so the capital measure performs the role other states assign to a franchise tax but is part of the same return…
Entity annual report
Yes
Filed on the anniversary date of the filing of the corporation's first annual report; a corporation formed on or after January 1, 2020 files its first annual report no later than 90 days after filing its certificate of incorporation, and a corporation formed before that date filed its first report no later than two…
Return due date
Published rule
May 15 - the 15th day of the fifth month after year end (the 15th day of the month following the federal due date)
Extension
Not verified
'Form CT-1120 EXT extends only the time to file the Connecticut Corporation Business Tax return. Form CT-1120 EXT does not extend the time to pay the amount of tax due.' Each corporation must submit payment of tax due or believed due with the extension…
Not verifiedZero activity / minimum tax
A return is still expected when no tax is due: 'If no tax is due, DRS may impose a $50 penalty for the late filing of any return or report required by law to be filed.'
Long-form guide in professional review
Dates, extensions and payments
Filing and payment dates stay separate wherever the source supports it.
- Filing
Return filing
May 15 - the 15th day of the fifth month after year end (the 15th day of the month following the federal due date)
15th day of the 5th month after year end for any year end other than June 30; a June 30 year end is due the 15th day of the 4th month after year end (October 15)
- Entity report
Entity report
Filed on the anniversary date of the filing of the corporation's first annual report; a corporation formed on or after January 1, 2020 files its first annual report no later than 90 days after filing its certificate of incorporation, and a corporation formed before that date filed its first report no later than two…
CGS 33-953(b) as amended by P.A. 19-40. Each domestic corporation (except banks, trust companies, insurance or surety companies, savings and loan associations and public service companies) and each authorized foreign corporation files…
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Frequently asked questions
Does Connecticut impose a corporate income tax?
Yes. Corporation Business Tax is the greater of the net income base (7.5 percent of apportioned Connecticut net income) or the capital base (0.21 percent of apportioned capital); a 10 percent surtax applies to companies with federal total… Form: Form CT-1120, Connecticut Corporation Business Tax Return (Form CT-1120CU for combined unitary filers).
Does Connecticut charge a franchise or privilege tax?
No. The official source consulted does not impose a franchise tax on corporations.
When is the Connecticut corporate return due?
May 15 - the 15th day of the fifth month after year end (the 15th day of the month following the federal due date)
Does an extension also postpone the tax payment?
No. The extension moves the filing date, not the payment date; unpaid tax can accrue penalty and interest.
Related states
Chosen because their corporate filing profile matches this one.
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