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Business Tax Return and Payment Due Dates


To avoid possible penalty and interest charges, ACH Debit taxpayers must initiate their transaction no later than midnight on, or before, the actual due dates below for the tax to be considered paid timely.

2019 Due Dates

For Period Ending:  EFT Due Date: 
December 31, 2018  Thursday, January 31, 2019 
January 31, 2019  Thursday, February 28, 2019
February 28, 2019  Monday, April 1, 2019 
March 31, 2019  Tuesday, April 30, 2019 
April 30, 2019  Friday, May 31, 2019 
May 31, 2019  Monday, July 1, 2019 
June 30, 2019  Wednesday, July 31, 2019 
July 31, 2019  Monday, September 2, 2019

2018 Due Dates

For Period Ending:  EFT Due Date 
August 31, 2018  Monday, October 1, 2018  
September 30, 2018  Wednesday, October 31, 2018
October 31, 2018  Friday, November 30, 2018 
November 30, 2018  Monday, December 31, 2018  
December 31, 2018  Thursday, January 31, 2019 

All Other Filers...

Quarterly Calendar Listing of Return and Due Dates

When it's time to file, please File Online. The Taxpayer Service Center (TSC) is free, fast, easy, and a secure way to conduct business with DRS.

Connecticut business taxpayers must electronically file and pay most Connecticut business tax returns using the Taxpayer Service Center.