February 2026: You can begin preparing and filing an extension when extensions become available in the 2025 software in February.
April 2026: The deadline for filing your extension is the same as the deadline for filing your tax return, April 15, 2026.
October 2026: If you filed an extension and the IRS accepted your extension, you must file your return by October 15, 2026 for it to be considered on time.
