Start Federal and Connecticut State Tax Returns
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Prepare and efile Your Connecticut Tax Return
The efile.com tax software makes it easy for you to efile your state tax return and use the correct state tax forms. Prepare and efile your Connecticut state tax return (resident, nonresident, or part-year resident) and Federal tax return together or separately at efile.com. View the federal tax return filing requirements.
Connecticut Income Tax Filing Deadline
The regular deadline to file a Connecticut state income tax return is April 15.
|Tax Deadline Date
||Type of Income Tax Return
||Filing Deadline / Due Date Description
|April 17, 2018
||2017 Connecticut State Tax Return
||Due date for Connecticut State Income Tax Returns - income tax filing deadline
|April 17, 2018
||2017 Connecticut State Tax Extension
||Due date for Connecticut extensions
|October 15, 2018
||2017 Connecticut State Tax Return
||Last day to efile a 2017 Connecticut State Income Tax Return for tax extension filers and late efilers
View all state tax return filing deadlines.
Find federal income tax return filing deadlines.
Tax Year 2017 Connecticut State Tax Forms
All of the following Connecticut state tax forms are supported by the efile.com software:
||Can I efile this form?
||Resident Income Tax Return
||Estimated Connecticut Income Tax Payment Coupon for Individuals
||Nonresident/Part-Year Resident Tax Return
||Electronic Filing Payment Voucher
||Underpayment of Estimated Income Tax by Individuals, Trusts, and Estates
||Alternative Minimum Tax Return
||Change of Address
||Request for Innocent Spouse Relief
||Connecticut Individual Use Tax Return
||Connecticut Income Tax Withholding Supplemental Schedule
||Connecticut Earned Income Tax Credit
Connecticut State Tax Forms that Cannot Be efiled
Connecticut State Tax Withholding Form
||Employee's Withholding Certificate
CT Tax Extension
||Connecticut Extension Instructions
||How to File
If you did not file a federal tax extension, you must use Form CT-1040 EXT to request a 6-month extension to file your CT tax return (not pay taxes owed). This also extends your time to file your individual use tax return. You can do this if you have a good reason for your request. If you do not owe any additional tax and you filed an extension for your federal tax return, you are not required to file a CT state extension. The extended tax return due date is October 15, 2018.
If you filed a federal extension form and you expect to owe no additional CT income tax, you're not required to file the CT state extension form.
To avoid penalty and interest fees, your entire bill must be paid on or before the tax return deadline. Any remaining balance is generally subject to a 10% penalty. There will also be an interest charge of 1% per month of a fraction of month until payment is made. If you efile your CT return and you're mailing your tax payment (check only), complete and attach Form CT-1040V (Electronic Filing Payment Voucher) with your payment.
Complete and submit Form CT-1040 EXT (if no federal extension submitted)
CT Tax Amendment
Connecticut state tax amendments can only be mailed; they cannot be efiled. Learn how to prepare and file an amended state Connecticut tax return.
Connecticut 2016 Previous Year Tax Forms
Connecticut tax forms for past Tax Years cannot be prepared and efiled online. You will need to print, fill out, and mail the forms to the Connecticut Department of Revenue Service.
Where's My Refund? - Check Your Connecticut State Tax Refund Status
If you efile a Connecticut tax return, your refund will generally be processed within 4 business days. If you file your return on paper, allow 10-12 weeks after it has been processed by the CT Department of Revenue Services.
Check your Connecticut tax return refund status online.
CT efile Error Codes
If your Connecticut state return was rejected, you will receive an error reject code. If you prepared and efiled your return on efile.com, we will provide you with an explanation of how to correct the error on your return. You may then resubmit your state return at no additional charge until it is accepted by the state.
View a list of all Connecticut State efile Income Tax Return Error Reject Codes.
Connecticut Tax Facts
CT Income Tax:
Individual income is taxed across six tax brackets at six graduated tax rates:
- 3% for the first $10,000 of taxable income
- 5% for taxable income between $10,001 and $50,000
- 5.5% for taxable income between $50,001 and $100,000
- 6% for taxable income between $100,001 and $200,000
- 6.5.% for taxable income between $200,001 and $250,000
- 6.9% for taxable income $250,001 and $500,000
- 6.99% for taxable income above $500,000
CT Sales Tax:
Connecticut has a state sales tax rate of 6.35% on the rental sale, lease, or rental of most goods. There is also a 7% luxury sales tax for the following purchases:
- Most motor vehicles costing more than $50,000
- Boats costing more than $100,000
- Jewelry (real & imitation) costing more than $5,000
- Apparel & footwear costing more than $1,000 (also applies to handbags, luggage, umbrellas, wallets, or watches costing more than $1,000)
More information on Connecticut Sales Tax
CT Sales Tax Holiday:
Connecticut has an annual one-week sales and use tax holiday. It usually occurs on the third week of August (from Sunday through Saturday). Certain items are exempt from Connecticut sales tax. However, the CT consumer will only receive the tax exemption if a specific total spending limit is met.
Refer to the chart below for Connecticut sales tax holidays for 2018.
|Sales Tax Holiday Dates
||Sales Tax Holiday Items Included
- Clothing and footwear: $100 or less
CT Personal Property Tax:
All personal property located within the state of Connecticut is taxable unless a statute specially exempts it. The tax varies based on each city and town in the state.
Odd Tax Fact:
The state of Connecticut has an online list of delinquent taxpayers.
CT State Tax Agency:
For more information, you can visit the website of The Connecticut Department of Revenue Services.
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