As we enter January 2026, it’s critical for businesses, employers, farmers, and fishermen to keep track of essential tax deadlines. Proper planning and adherence to these deadlines can ensure compliance and avert unnecessary penalties.

January 15 – Employer’s Monthly Deposit Deadline
Employers subject to monthly deposit rules must make deposits of Social Security, Medicare, and withheld income taxes for December 2025 by January 15. Additionally, this is the due date for nonpayroll withholding deposits for December 2025, if applicable under the monthly rule. All employment tax deposits must be made electronically, except for employers with a deposit liability of less than $2,500 per return period, who may choose to remit payments quarterly or annually.

January 15 – Farmers and Fishermen
For farmers and fishermen, January 15 is the deadline to pay estimated tax for 2025 using Form 1040-ES. While the final filing of the 2025 tax return (Form 1040 or 1040-SR) is due by April 15, failure to pay estimated tax by January 15 requires filing the 2025 return by March 2, 2026, to sidestep penalties.

Regarding Weekends & Holidays:
If a tax deadline falls on a Saturday, Sunday, or legal holiday, the due date is extended to the next business day that is not a holiday.

Considerations for Disaster Area Extensions:
Taxpayers in federally-designated disaster areas receive extended due dates. To verify if an extension applies to your area, visit the FEMA website and the IRS website for the latest updates.