Filing a clean extension is a five-minute task that prevents four-figure penalties. Here's the whole system.
Which form, which deadline
- Form 7004 — businesses. S-corps (1120-S) and partnerships (1065) file by March 15 and get to September 15. C-corps (1120) file by April 15 and get to October 15. The foreign-owned LLC's pro-forma 1120 + 5472 extends with 7004 too.
- Form 4868 — individuals (1040, 1040-NR with wage withholding), April 15 → October 15.
The payment rule
An extension moves the filing deadline, not the payment deadline. Tax owed is still due in April (or March for entities that owe). The play: estimate what you'll owe, pay it with the extension, square up when the real return is done. Overpay slightly rather than under — the failure-to-pay penalty plus interest run from day one otherwise.
Why professionals extend on purpose
- K-1s from other entities arrive late — filing before they exist means amending after
- Clean books beat rushed books; extensions buy accuracy
- Certain elections and retirement contributions get more runway on an extended return
State extensions
Many states honor the federal extension automatically; several require their own form or payment. Check each state you file in — the federal 7004 alone doesn't cover everyone.
The bottom line
Right form, on time, with a payment attached. MOREOFTAX files extensions for clients as a default part of tax-season protection — and the estimate that goes with them.
Deadline coming fast?
We can file your extension with a payment estimate today, then finish the return properly.
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