December 2025 Business Due Dates

December brings key business tax deadlines, including corporate estimated tax payments and monthly payroll tax deposits. Plus, a reminder to complete year-end actions before closures on December 31.

December 15 - Corporations

The fourth installment of estimated tax for 2025 calendar year corporations is due.

December 15 - Social Security, Medicare and Withheld Income Tax

If you are an employer and the monthly deposit rules apply, December 15 is the due date for you to make your deposit of Social Security, Medicare, and withheld income tax for November 2025. This is also the due date for the nonpayroll withholding deposit for November 2025 if the monthly deposit rule applies.

December 31 - Caution! Last Day of the Year

If the actions you wish to take cannot be completed on the 31st or in a single day, you should consider taking action earlier than December 31st, as some financial institutions may be closed  that day.

Weekends & Holidays:

If a due date falls on a Saturday, Sunday or legal holiday, the due date is automatically extended until the next business day that is not itself a legal holiday. 

Disaster Area Extensions:

Please note that when a geographical area is designated as a disaster area, due dates will be extended. For more information whether an area has been designated a disaster area and the filing extension dates visit the following websites:

FEMA: https://www.fema.gov/disaster/declarations
IRS: https://www.irs.gov/newsroom/tax-relief-in-disaster-situations  

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