• January 15th: due date to pay 4th quarter estimated taxes.
• January 31st:
  • Due date to send out 1099s and W-2s to recipients.
  • Due date to file 1099s/1096s with amounts in Box 7 and W-2s/W-3s with the IRS.
• February 28th: due date to file 1099s/1096s that do not have amounts in Box 7 if you are paper filing.
• March 15th:
  • Due date to file S-Corp (1120S) and partnership (1065) returns
  • Due date to elect S-Corp status for existing corporations or LLCs.
• April 1st: due date to file 1099s/1096s that do not have amounts in Box 7 if you are filing electronically.
• April 15th:
  • Due date to file individual (1040), trust (1041), and C-Corp (1120) returns.
  • Last day to make HSA contributions and contributions to the majority of retirement plans.
  • Due date to pay 1st quarter estimated payments.
• May 15th: due date to file most nonprofit returns (Form 990).
• June 17th: due date to pay 2nd quarter estimated payments.
• September 16th:
  • Due date for extended S-Corp and partnership tax returns.
  • Due date to pay 3rd quarter estimated payments.
• October 1st: due date for extended trust returns.
• October 15th:
  • Due date for extended individual tax returns and C-Corp returns.
• November 15th: due date to file extended nonprofit returns.

A reminder as regards the April 15th deadline: an extension is an extension to file, not an extension to pay. If you file an extension and still owe money you will be assessed the failure-to-pay penalty of 0.5% per month on the balance. This is a huge improvement over the 5% per month failure-to-file penalty – so by all means file an extension (or get us to file one for you) if you need one.