Form 1040-ES, Estimated Tax Payment for Individuals (2025 #4)
February 2, 2026
Form W-2 (to employees)
Form W-3 (to IRS)
Form 1099-NEC (to recipients)
Form 1099-MISC
March 16, 2026
Forms 1042, 1042-S
Form 1065, Partnership Income Tax Return
Form 1120-S, S-Corporation Income Tax Return
April 15, 2026
Form 1040, Individual Income Tax Return
Form 1040-ES, Estimated Tax Payment for Individuals (2026 #1)
Form 1120, C-Corporation Income Tax Return
Form 1120-W, Estimated Tax Payment for C-Corporation (2026 #1)
Form 1065-V, Form 1120-ST-V, Estimated Tax Payment for Partnerships and S Corporations Electing the Illinois Pass-Through Entity Tax (2026 #1)
May 15, 2026
Form 990, Exempt Organization
June 15, 2026
Form 1040-ES, Estimated Tax Payment for Individuals (2026 #2)
Form 1120-W, Estimated Tax Payment for C-Corporation (2026 #2)
Form 1065-V, Form 1120-ST-V, Estimated Tax Payment for Partnerships and S Corporations Electing the Illinois Pass-Through Entity Tax (2026 #2)
September 15, 2026
Form 1040-ES, Estimated Tax Payment for Individuals (2026 #3)
Form 1120-W, Estimated Tax Payment for C-Corporation (2026 #3)
Form 1065, Partnership Income Tax Return – Extended Due Date
Form 1120-S, S-Corporation Income Tax Return – Extended Due Date
Form 1065-V, Form 1120-ST-V, Estimated Tax Payment for Partnerships and S Corporations Electing the Illinois Pass-Through Entity Tax (2026 #3)
October 15, 2026
FBAR FinCen Form 114 (e-File), Foreign Bank Account Reporting
Form 1120, C-Corporation Income Tax Return – Extended Due Date
Form 1040, Individual Income Tax Return – Extended Due Date
November 16, 2026
Form 990, Exempt Organization – Extended Due Date
December 15, 2026
Form 1120-W, Estimated Tax Payment for C-Corporation (2026 #4)
Form 1065-V, Form 1120-ST-V, Estimated Tax Payment for Partnerships and S Corporations Electing the Illinois Pass-Through Entity Tax (2026 #4)
January 15, 2027
Form 1040-ES, Estimated Tax Payment for Individuals (2026 #4)
Fiscal Year Ends
Fiscal Year 990: 4 ½ months after year end (10 ½ months if extended)
Fiscal Year 1120: 3 ½ months after year end (9 ½ months if extended)
Fiscal Year 1120S or 1065: 2 ½ months after year end (8 ½ months if extended)
For over 50 years, Dugan + Lopatka has leveraged comprehensive services and industry-specific expertise to give our clients a competitive advantage. To learn how smart tax planning can help your business achieve its goals, contact our team today.
