Tax extensions
Tax extension checklist
An extension moves the filing deadline, not the payment deadline. A client who needs more time still has to estimate the tax owed and pay it by the original due date, or interest and penalties start. This checklist covers what to collect for an individual, business or trust extension, and what the client still owes after the extension is filed.
Who sends itSent by the tax preparer to a client who cannot file by the original deadline, before the original due date, so the extension and the payment are filed on time.
0 of 20 ticked
01Individual extension
02Business extension
03Trust and estate extension
04After the extension is filed
What firms get wrong
- Filing the extension without estimating and paying the tax, which leaves the client with a failure-to-pay penalty.
- Missing a state extension because the federal extension was filed.
- Using Form 4868 for a business return instead of Form 7004.
- Waiting for the missing K-1 before filing the extension, when the extension could have been filed on time.
- Treating the extended date as the payment date and paying the tax in October instead of April.
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Questions about this checklist
Does an extension give more time to pay?
No. An extension gives more time to file the return, but the tax owed is still due by the original deadline. The client should estimate the tax and pay it with the extension to limit interest and penalties.
When is the extended deadline for an individual return?
Form 4868 gives an automatic six-month extension, so a 2026 individual return that was due April 15, 2027 can be filed by October 15, 2027. The extension does not change the payment deadline.
Does a state accept the federal extension?
Some states accept the federal extension and some require their own form or payment. Check the state's instructions for each state where the client files.
What if the client cannot pay the tax owed?
The client should still file the extension and pay what they can by the original deadline. Ask the firm about an installment agreement or another payment option before the deadline passes.
Do 1099s and W-2s get an extension too?
The January 31 information return deadline is separate from the income tax return extension. A business that needs more time for 1099s or W-2s should check the specific extension rules for those forms.
Sources
Checked November 3, 2026. Tax rules, forms and thresholds change; confirm them with the IRS or your tax software before relying on them.
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