2017 Connecticut Quarterly Estimated Tax Payments

1. Am I required to make 2017 Connecticut (CT) quarterly estimated tax payments?

The CT Department of Revenue Services (DRS) requires you to make quarterly estimated tax payments for calendar year 2017 if both of the following apply:

  • you expect to owe at least $1,000 in State of CT income tax for 2017, after subtracting CT tax withholding and credits, and
  • you expect CT withholding and credits to be less than the smaller of:
    • 90% of the income tax to be shown on your 2017 CT tax return, or
    • 100% of the income tax shown on your 2016 CT tax return (only applies if your 2016 tax return covered 12 months’ otherwise; utilize the 90% test above only). Note:  If you were a nonresident or part-year resident of Connecticut in 2016 and you did not have Connecticut-sourced income during 2016, you must use the 90% test above only.

You are not required to make CT estimated tax payments if:

  • You were a CT resident during the 2016 taxable year and you did not file a 2016 CT income tax return because you had no CT income tax liability, or
  • You were a nonresident or part-year resident with CT source income during the 2016 taxable year and you did not file a 2016 income tax return because you had no CT income tax liability.

2. How do I calculate the amount of my CT quarterly estimated tax payments?

To calculate your State of CT quarterly estimated tax payments, you must estimate your adjusted gross income, deductions, and credits for the calendar year 2016. 2017 Form CT 1040-ES includes an Estimated Connecticut Income Tax Worksheet to help you calculate your CT estimated tax payments. For examples of completed estimated tax worksheets, please refer to the Examples section of this site.

Frequently Asked Questions

1. What are the filing dates for CT quarterly estimated tax payments?

Payment Period Due Date
January 1 - March 31, 2017 April 18, 2017
April 1 - May 31, 2017 June 15, 2017
June 1 - August 31, 2017 September 15, 2017
September 1 - December 31, 2017 January 16, 2018*

*You do not have to make the payment due January 16, 2018 if you file your 2017 CT tax return by January 31, 2018, and pay the entire balance due with your return.

2. How do I make CT quarterly estimated tax payments?

The CT DRS provides three (3) methods to pay quarterly estimated taxes:

3. What if I do not pay enough CT income tax in a timely manner for the calendar year 2017?

Generally, if you do not pay enough tax either through withholding or making estimated tax payments, you may be charged interest. Interest is calculated at a rate of 1% per month on the underpayment of tax.

4. How do I obtain additional information regarding CT quarterly estimated tax payments?

For additional information regarding CT quarterly estimated tax payments, please refer to the 2017 Form CT-1040ES instructions and also CT IP 2011(26) or consultant your personal tax advisor.