Last Day To File Taxes 2024 Timeline. This is the official deadline for filing federal income tax returns for the 2023 tax year.  — december 31, 2024, is the last day of the tax year and is also the last day to make contributions to your 401 (k) plan or to incur expenses you expect to deduct when.

 — the irs begins accepting tax year 2023 returns on jan. This is the official deadline for filing federal income tax returns for the 2023 tax year.