To request an extension of time to ﬁle your return, you must ﬁle Form CT-1040 EXT, Application for Extension of Time to File Connecticut Income Tax Return for Individuals, and pay all the tax you expect to owe on or before the due date.
Form CT-1040 EXT extends only the time to ﬁle your return; it does not extend the time to pay your tax due.
You do not need to ﬁle Form CT-1040 EXT if you:
- Have requested an extension of time to ﬁle your 2018 federal income tax return and you expect to owe no additional Connecticut income tax for the 2018 taxable year after taking into account any Connecticut income tax withheld from your wages and any Connecticut income tax payments you have made, and any Pass-Through Entity Tax Credit; or
- Pay your expected 2018 Connecticut income tax due using a credit card on or before the due date.
You must ﬁle Form CT-1040 EXT
- Did not request an extension of time to ﬁle your federal income tax return, but you are requesting an extension of time to ﬁle your Connecticut income tax return; or
- Have requested an extension of time to ﬁle your federal income tax return but you expect to owe additional Connecticut income tax for 2018 and wish to submit a payment with Form CT-1040 EXT.
If you ﬁle an extension request with a payment after the due date, generally April 15, Connecticut will deny your extension request.