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2018 Connecticut Quarterly Estimated Tax Payments
1. Am I required to make 2018 Connecticut (CT) quarterly estimated tax payments?
The CT Department of Revenue Services (DRS) requires you to make quarterly estimated tax payments for calendar year 2018 if both of the following apply:
- you expect to owe at least $1,000 in State of CT income tax for 2018, 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 2018 CT tax return, or
- 100% of the income tax shown on your 2017 CT tax return (only applies if your 2017 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 2017 and you did not have Connecticut-sourced income during 2017, 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 2017 taxable year and you did not file a 2017 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 2017 taxable year and you did not file a 2017 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 2018. 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, 2018||April 17, 2018|
|April 1 - May 31, 2018||June 15, 2018|
|June 1 - August 31, 2018||September 17, 2018|
|September 1 - December 31, 2018||January 15, 2019*|
*You do not have to make the payment due January 15, 2019 if you file your 2018 CT tax return by January 31, 2019, 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:
- You may pay by check and mail your payment with a payment voucher form, Form CT-1040ES;
- You may pay using your credit or debit card via a pay-by-phone system or the Internet; or
- You may pay electronically by using Taxpayer Service Center (TSC)-IND
3. What if I do not pay enough CT income tax in a timely manner for the calendar year 2018?
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?