2027 calendar · Illinois

Business Tax Deadlines
2027 Calendar

Every federal, Illinois and trucking deadline for small businesses in one list. Add it to your phone and get each date automatically.

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All Dates

2027 Deadlines

Dates that fall on a weekend are moved to the next business day. Fiscal-year businesses have different dates. Check with us before relying on a date for your situation.

January 15, 2027Estimated taxQ4 2026 estimated tax payment (Form 1040-ES)
February 1, 2027Payroll & 1099W-2 and 1099-NEC to workers and the IRS; Form 941 for Q4
February 1, 2027TruckingIFTA return for Oct–Dec 2026
March 15, 2027ReturnsS-Corp (1120-S) and partnership (1065) returns, or extension (Form 7004)
March 15, 2027ReturnsLast day to elect S-Corp status for 2027 (Form 2553)
April 15, 2027ReturnsPersonal returns (1040, IL-1040), C-Corp returns (1120), Q1 estimated tax
April 30, 2027TruckingIFTA return for Jan–Mar; Form 941 for Q1
June 15, 2027Estimated taxQ2 estimated tax payment
August 2, 2027TruckingIFTA return for Apr–Jun; Form 941 for Q2
August 31, 2027TruckingForm 2290 heavy vehicle use tax (trucks first used in July)
September 15, 2027ReturnsExtended S-Corp and partnership returns; Q3 estimated tax
October 15, 2027ReturnsExtended personal and C-Corp returns
November 1, 2027TruckingIFTA return for Jul–Sep; Form 941 for Q3