IP 2010(27)

Estimated Connecticut Income Taxes

This publication has been superseded by IP 2011(26)

Filing Status Options: The Connecticut filing status options are single, filing jointly for federal and Connecticut, filing jointly for Connecticut only, filing separately for federal and Connecticut, filing separately for Connecticut only, head of household, and qualifying widow(er) with dependent child.

Parties to a civil union recognized under Connecticut law or spouses in a marriage recognized under Public Act 2009-13 must file their Connecticut income tax returns as if they were entitled to the same filing status accorded spouses under the Internal Revenue Code (IRC). This means that, for purposes of calculating their Connecticut income tax liability, parties to a civil union or spouses in a marriage recognized under Public Act 2009-13 must recompute their federal income tax liability as married filing jointly or married filing separately. The filing status for individuals who are parties to a civil union recognized under Connecticut law or in a marriage recognized under Public Act 2009-13 is either filing jointly for Connecticut only or filing separately for Connecticut only. Parties to a civil union or spouses in a marriage recognized under Public Act 2009-13 may not calculate their Connecticut income tax liability as single or, if applicable, head of household filers although this will be their filing status for federal income tax purposes.

1. What is estimated tax: Connecticut law requires taxpayers to pay Connecticut income tax during the year through withholding or estimated tax payments, or both. Most employees have these taxes withheld automatically from their paychecks. If you are self-employed, receive a pension or annuity, or receive unemployment compensation and have not elected Connecticut income tax withholding, or you receive any other income from which Connecticut income tax is not withheld, you probably should make estimated income tax payments.

Because it is difficult to determine your exact tax liability before the end of the year, you may make estimated tax payments during the year based upon what you expect to earn in the current year or what you actually earned in the prior year. When you file your annual income tax return, you report your estimated tax payments. If you have overpaid estimated tax during the year, you will receive a refund. If you underpaid your taxes during the year, you will have to pay the tax you owe and you may have to pay interest on the amount of the underpayment.

2. Who should pay estimated tax: You must make estimated Connecticut income tax payments if the Connecticut income tax you owe after tax credits minus Connecticut income tax withheld is $1,000 or more, and you expect your Connecticut income tax withheld to be less than your required annual payment.

3. Your required annual payment: Your required annual payment is the lesser of:

You do not have to make estimated income tax payments if you did not file a Connecticut income tax return for the preceding taxable year because you had no Connecticut income tax liability and you were either:

If you were a nonresident or part-year resident and you did not have Connecticut-sourced income in the preceding taxable year, you must use 90% of the income tax shown on your income tax return for the current taxable year as your required annual payment.

In estimating your Connecticut income tax liability, you may take into consideration any allowable credits that reduce your income tax liability. These credits include a credit for income taxes paid to a qualifying jurisdiction, the credit for prior year Connecticut alternative minimum tax, and other allowable credits as discussed in Special Notice 2010(3), 2010 Legislation Affecting the Income Tax.

4. What types of income may not be subject to withholding and may require estimated tax payments: The list below indicates many (but not all) types of income that may not be subject to Connecticut income tax withholding and may require you to pay estimated tax:

To avoid filing estimated taxes, you may ask your employer or pension plan payer to withhold additional amounts from your wages or pension income to cover the taxes on other income. You can make this change by providing your employer or pension payer with a revised Form CT-W4, Employee’s Withholding Certificate, or Form CT-W4P, Withholding Certificate for Pension or Annuity Payments.

Retired federal civil service employees must contact the U.S. Office of Personnel Management at 1-888-767-6738 to start, stop, or make changes to Connecticut income tax withholding.

5. How do I estimate my tax: You need Form CT-1040ES, Estimated Connecticut Income Tax Payment Coupon for Individuals, to calculate your estimated tax payments. The form instructions include a worksheet for computing your estimated tax payments, exemption and credit tables, and a coupon to mail with your estimated payments. You can also go to the Department of Revenue Services (DRS) website to use the Taxpayer Service Center (TSC) to file and pay electronically or you may download a paper Form CT-1040ES from the DRS website.

If you made estimated Connecticut income tax payments by mail last year, you will receive coupons in mid-January. Each coupon is preprinted with your name, address, and Social Security Number. If you made estimated tax payments electronically, you will not receive coupons in the mail.

6. When do I pay my estimated income tax: You must make your first estimated income tax payment on or before April 15. You can pay all of your estimated tax with the first payment or pay the tax in four installments, due April 15, June 15, September 15, and January 15. Taxpayers who are not calendar year filers should use the same filing dates as they do for federal income tax purposes. An estimate is considered timely filed if received on or before the due date, or if the date shown by the U.S. Postal Service cancellation mark is on or before the due date. If the due date falls on a Saturday, Sunday, or legal holiday, the next business day is the due date.

7. How much should I pay with each installment: You must pay 25% of the required annual payment with each installment. Your installments should be made as follows:

If on or before March 1 following the end of the taxable year you file a Connecticut income tax return and pay in full the amount computed on the return as payable, you will not be subject to interest for not making an estimated income tax payment. For more information, see Informational Publication 2010(16), Farmer’s Guide to Sales and Use Taxes, Motor Vehicle Fuels Tax, Estimated Income Tax, and Withholding Tax.

You need Form CT-2210, Underpayment of Estimated Income Tax by Individuals, Trusts, and Estates. Check Box A, Part I, of Form CT-2210, attach the form to your income tax return, and check the box for Form CT-2210 on the front of your Connecticut income tax return below the name and address section. This notifies DRS that your estimated income tax is based on the annualized income installment method.

9. What happens if I underestimate my tax: If you are required to make estimated income tax payments and you do not pay enough tax during the year through withholding or estimated tax payments, or both, by the installment due date, you may be charged interest. This is true even if you are due a refund when you file your tax return. Interest is calculated separately for each installment from the due date of that installment until the earlier of April 15 or the date on which the underpayment is paid. Therefore, you may owe interest for an earlier installment even if you paid enough tax with a later installment to make up the underpayment. Interest at 1% per month, or fraction of a month, applies to the underpayment(s). If you file your income tax return for the taxable year on or before January 31 of the following year and pay the amount computed on the return as payable for the taxable year, no interest will be charged for failure to make the fourth required installment. This does not apply to taxpayers paying estimated Connecticut income taxes as farmers and fishermen.

10. May I apply an overpayment in the prior year to the next year's estimate: Yes. When you file your return, you may elect to apply overpayments of Connecticut income tax to your succeeding year estimated tax. If you file your Connecticut income tax return on or before April 15 or if you file a timely request for extension of time to file and your income tax return is filed within the extension period, the overpayment will be treated as estimated tax paid on April 15. Your election to apply overpayments to your succeeding year estimated income tax is irrevocable. 

Related Forms and Publications:

Effect on Other Documents: Informational Publication 2009(35) is superseded and may not be relied upon after the date of issuance of this publication.

Effect of This Document: An Informational Publication issued by DRS addresses frequently-asked questions about a current position, policy, or practice, usually in a less technical question and answer format.

For Further Information: Call DRS during business hours, Monday through Friday

TTY, TDD, and Text Telephone users only may transmit anytime by calling 860-297-4911. 

IP 2010(27)
Income Tax
Estimated Income Tax
Issued: 12/30/10