This gives you until October 15 to file without penalties. You'll receive an electronic acknowledgment once you.A tax extension moves your federal taxfiling deadline out six months to Oct. 15. The deadline for requesting an extension is April 15. How to file a tax return extension for C corps. Such filers should fill out the Form 4868 and send it to an address listed on the IRS website. The taxpayer is automatically provided a six-month extension of time to file. This is an extension of time to file, not to pay. The deadline to file an extension is April 15, 2025 – the same as the original tax deadline. You can use FreeTaxUSA any time until the October 15, 2025 deadline to file an extended tax return.