January 15

Final payment of the prior year estimated tax for individuals.

January 31

Due date of employers' fourth quarter payroll tax returns.

March 15

Due date of prior year tax return for calendar year corporations. (Forms 1120 or 1120S)

April 30

Due date of employers' first quarter payroll tax return.

June 16

Second payment of the current year estimated tax for calendar year individuals and corporations.

July 31

Due date of employers' second quarter payroll tax return.

August 15

Due date for prior year tax return for calendar year individuals that file an extension.

September 15

Third payment of the current year estimated tax for calendar year individuals and corporations and partnerships. Due date of prior year tax return for calendar year corporations that filed an extension.

October 15

Final due date for prior year tax return for calendar year individuals that filed a second extension (no more extensions).

October 31

Due date of employers' third quarter payroll tax returns.

December 15

Final payment of the current year estimated tax for corporations.