Calendar-year corporations: File a 2024 income tax return (Form 1120) or file for an automatic six-month extension (Form 7004). Pay any tax due.

Calendar-year corporations: Pay the first installment of 2025 estimated income taxes and complete Form 1120-W for the corporation’s records.

Calendar-year trusts and estates: File a 2024 income tax return (Form 1041) or file for an automatic five-and-a-half-month extension (six-month extension for bankruptcy estates) (Form 7004). Pay any tax due.

Employers: Deposit Social Security, Medicare and withheld income taxes for March if the monthly deposit rule applies.

Employers: Deposit nonpayroll withheld income tax for March if the monthly deposit rule applies.

Household employers: File Schedule H, if wages paid equal $2,700 or more in 2024 and Form 1040 isn’t required to be filed. For those filing Form 1040, Schedule H is to be submitted with the return and is thus extended to the due date of the return.

Individuals: File a 2024 income tax return (Form 1040 or Form 1040-SR) or file for an automatic six-month extension (Form 4868). (Taxpayers who live outside the United States and Puerto Rico or serve in the military outside these two locations are allowed an automatic two-month extension without requesting one.) Pay any tax due.

Individuals: Pay the first installment of 2025 estimated taxes (Form 1040-ES) if not paying income tax through withholding or not paying sufficient income tax through withholding.

Individuals: Make 2024 contributions to a traditional IRA or Roth IRA (even if a 2024 income tax return extension is filed).

Individuals: Make 2024 contributions to a SEP or certain other retirement plans (unless a 2024 income tax return extension is filed).

Individuals: File a 2024 gift tax return (Form 709), if applicable, or file for an automatic six-month extension (Form 8892). Pay any gift tax due. File for an automatic six-month extension (Form 4868) to extend both Form 1040 and Form 709 if no gift tax is due.