By what date should I file a tax extension for my business?

Your tax extension must be filed on or before the original due date of your business tax return. S corporation, Multi Member LLC’s & Partnerships tax returns are all due by March 15, which means any request for a tax extension has to be filed by March 15. C corporation tax returns are due by April 15, which means a tax extension must be filed by that same date in order to be approved. Trusts and estates filing IRS Form 1041 also have an April 15 deadline. If you e-file your tax extension, technically it should be submitted by midnight (local time zone) on the due date but a little known secret is that the IRS accepts tax extension requests up to 5 days after the deadline. They do this to allow for any corrections to previously filed tax returns and extension but the reality is, the will also accept initial filings. If you file your extension request and it’s rejected as being too late, will refund your fee, no questions asked!