October 10, 2024

Individuals – Report September tip income of $20 or more to employers (Form 4070).

October 15, 2024

Individuals – File a 2023 income tax return (Form 1040 or Form 1040-SR) if an automatic six-month extension was filed (or if an automatic four-month extension was filed by a taxpayer living outside the United States and Puerto Rico). Pay any tax, interest and penalties due.

Individuals – Make contributions for 2023 to certain existing retirement plans or establish and contribute to a SEP for 2023 if an automatic six-month extension was filed.

Individuals – File a 2023 gift tax return (Form 709) and pay any tax, interest and penalties due if an automatic six-month extension was filed.

Calendar-year bankruptcy estates – File a 2023 income tax return (Form 1041) if an automatic six-month extension was filed. Pay any tax, interest and penalties due.

Calendar-year C corporations – File a 2023 income tax return (Form 1120) if an automatic six-month extension was filed. Pay any tax, interest and penalties due.

Calendar-year C corporations – Make contributions for 2023 to certain employer-sponsored retirement plans if an automatic six-month extension was filed.

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

Employers – Deposit nonpayroll withheld income tax for September if the monthly deposit rule applies.

Employers – Report Social Security and Medicare taxes and income tax withholding for third quarter 2024 (Form 941) and pay any tax due if all of the associated taxes due weren’t deposited on time and in full.