December 2023 Business Due Dates

December 1 - Employers

During December, ask employees whose withholding allowances will be different in 2024 to fill out a new Form W4 or Form W4(SP). 

December 15 - Social Security, Medicare and Withheld Income Tax


If the monthly deposit rule applies, deposit the tax for payments in November.

December 15 - Nonpayroll Withholding

If the monthly deposit rule applies, deposit the tax for payments in November.

December 15 - Corporations

The fourth installment of estimated tax for 2023 calendar year corporations is due.

December 31 - Last Day to Pay Deductible Expenses for 2023  

Last day to pay deductible expenses for the 2023 return (doesn’t apply to IRA, SEP or Keogh contributions, all of which can be made after December 31, 2023). 

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, which is a Sunday and many financial institutions may be closed on Friday the 29th, as well as Saturday the 30th.

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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