Essential December 2025 Tax Deadlines for Businesses

The month of December is pivotal for businesses with several critical tax deadlines, notably those for corporate estimated tax payments and monthly payroll tax deposits. Additionally, businesses should take note of completing necessary year-end tasks before the financial and administrative closures on December 31st.

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December 15 - Corporations

The fourth installment for the estimated tax obligations of calendar year corporations is due on December 15th. Timely payments are crucial to avoid penalties and interest.

December 15 - Social Security, Medicare, and Withheld Income Tax

If you operate under the monthly deposit rules as an employer, you'll need to make your deposit for Social Security, Medicare, and withheld income taxes by December 15th for November 2025. This same deadline applies for the nonpayroll withholding deposit if the monthly deposit rule applies.

December 31 - Year-End Caution

The last day of the year, December 31st, is significant for ensuring all actionable items are completed in time. Be aware that some financial institutions may not operate on this day. Prior planning is advisable since some tasks might require several days to finalize.

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Weekend and Holiday Adjustments:

If any due date coincides with a Saturday, Sunday, or legal holiday, the deadline will typically extend to the next business day, excluding holidays.

Disaster Area Extensions:

In cases where a location is declared a disaster area, tax obligations may be extended. For information regarding disaster declarations and applicable extensions, consult:
FEMA: FEMA disaster declarations
IRS: IRS tax relief for disasters

Adhering to these deadlines and guidelines is imperative for efficient business management and effective tax strategy execution. For tailored advice and personalized tax planning, consulting tax professionals like those at New Beginnings One Stop Tax Help can provide specialized support and peace of mind.

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