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
Deposit the fourth installment of estimated income tax for 2015. A worksheet, Form 1120-W, is available to help you estimate your tax for the year.
Fiscal-Year Taxpayers:
If you use a fiscal year (rather than the calendar year) as your tax year, you should change some of the dates in this calendar. Use the following general guidelines to make these changes.
December 31
Deduction deadline:
The last date to make payments that can be deducted from your 2014 return.