December 15:

4th Quarter 2015 estimated tax payments are due for calendar-year corporations

November payroll and nonpayroll withholding taxes are due

January 15:

4th Quarter 2015 estimated tax payments are due for individuals and calendar-year estates and trusts

December payroll and nonpayroll withholding taxes are due

February 1:

W-2s and 1099s are due to employees and other payees

Employer Form 941 (for 4th Quarter) and Form 944 (for 2015) are due

Employer Form 940 is due for 2015

Form 945 to report income withheld for 2015 on all nonpayroll items.

*If the appropriate taxes are paid in full, deposited on time, and filed properly, Forms 940, 941,943, 944, and 945 are not due until February 10th.