2026 small business tax deadlines: a federal filing calendar

Because January 31, 2026 falls on a Saturday, key January 31 reporting deadlines move to Monday, February 2, 2026. Employers generally furnish 2025 Forms W-2 to employees and file Copy A with the Social Security Administration by that date. Form 1099-NEC for reportable 2025 nonemployee compensation is also due to the IRS and recipient by February 2, 2026.

For calendar-year entities, March 15 falls on a Sunday in 2026, so the deadline moves to March 16. Calendar-year partnerships file Form 1065 and furnish Schedule K-1. Calendar-year S corporations file Form 1120-S and furnish shareholder K-1s. March 16 is also the general 2026 deadline for a calendar-year entity making a timely S corporation election effective January 1, 2026.

A calendar-year C corporation generally files Form 1120 by April 15. Individuals, including many sole proprietors and owners receiving pass-through income, generally file the 2025 Form 1040 by April 15, 2026. The first 2026 individual estimated-tax installment is also due April 15.

• April 15, 2026 — first 2026 individual estimated-tax installment.
• June 15, 2026 — second installment.
• September 15, 2026 — third installment.
• January 15, 2027 — fourth installment for 2026.

Form 941 is generally due by the last day of the month after each calendar quarter: April 30, July 31, October 31, and January 31, subject to weekend/holiday rules and a potential additional 10 days when all deposits were made on time. Payroll tax deposit deadlines are separate and depend on the employer's deposit schedule.

Form 7004 can provide an automatic filing extension for many business returns, but an extension to file generally does not extend the time to pay tax. A useful calendar therefore tracks return deadlines, payment deadlines, estimated-tax dates, payroll deposit dates, and state obligations separately.