Key Business Tax Deadlines for December 2025

As December approaches, businesses must prepare for significant tax deadlines, including vital corporate tax payments and necessary payroll tax deposits. It is crucial to complete year-end financial tasks well ahead of the December 31 deadline to ensure smooth operations and compliance.

December 15 - Corporate Estimated Tax Obligation

Corporations should mark their calendars for the fourth estimated tax payment for the 2025 fiscal year, due on December 15. This deadline is non-negotiable for staying in good standing with federal tax requirements.

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December 15 - Payroll Tax Deposits

Employers following monthly deposit rules must ensure their Social Security, Medicare, and withheld income taxes for November 2025 are deposited by December 15. This deadline also applies to nonpayroll withholdings if applicable. Ensuring these deposits are timely is crucial to avoid penalties.

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December 31 - Conclusion of the Fiscal Year

The final day of the fiscal year, December 31, serves as a cautionary reminder. Any critical financial maneuvers or end-of-year decisions requiring execution should be completed before this date, especially since many financial institutions may close early.

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Adjustments for Non-Business Days

Deadlines falling on weekends or legal holidays automatically move to the next business day, which is typically the subsequent Monday or day after the holiday, as applicable.

Disaster Area Date Extensions

In designated disaster areas, due dates may extend to accommodate affected businesses. Consult the FEMA and IRS guidelines for updates on crucial relief measures and extensions.

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