December 10

Employees who work for tips - If you received $20 or more in tips during November, report them to your employer. You can use Form 4070.

December 15

Corporations - Deposit the fourth installment of estimated income tax for 2020. A worksheet, Form 1120-W, is available to help you estimate your tax for the year.

Employers Social Security, Medicare, and withheld income tax - If the monthly deposit rule applies, deposit the tax for payments in November.

Employers Nonpayroll withholding - If the monthly deposit rule applies, deposit the tax for payments in November.