FID-EXT: Declaration of Estimated Tax Return Extension (2025)
Delaware · Delaware Division of Revenue · Used for tax years 2025
Form FID-EXT is an application for an automatic extension of time to file a Delaware fiduciary income tax return, Form FID-TAX. It identifies the trust or estate and fiduciary, requests the filing extension, and records the installment payment amount.
Who files this form
FID-EXT is for a fiduciary requesting an automatic extension of time to file Delaware Form FID-TAX, the fiduciary income tax return.
When it's due
For tax year 2025:
- April 30, 2026: FID-EXT must be filed by this date.
- October 15, 2026: The extended filing date requested on FID-EXT for Form FID-TAX.
The form also provides spaces for fiscal-year dates.
What you'll need
Have the information requested on the form ready:
- Taxpayer ID and name of the trust or estate.
- Fiduciary’s name, title and mailing address.
- Tax year and any applicable fiscal-year dates.
- Installment amount and installment payment amount.
- Signer’s title, email address and phone number.
How to file
Complete FID-EXT and have the fiduciary officer or representative sign and date it. Keep a copy for your records.
Mail the completed form with remittance payable to:
Delaware Division of Revenue
PO Box 2044
Wilmington, DE 19899-2044
Common mistakes
- Do not cut the page.
- Do not forget to sign the return.
- Keep a copy for your records.
Questions people ask
Which return does FID-EXT extend?
It requests an automatic extension of time to file Form FID-TAX, the Delaware fiduciary income tax return.
What extended filing date does the 2025 form request?
The form requests an extension to October 15, 2026, for tax year 2025. It also has spaces for fiscal-year dates.
Who signs FID-EXT?
The signature line is for the fiduciary officer or representative. The signer declares under penalties of perjury that they have examined the return, including accompanying schedules and statements, and believe it is true, correct and complete.
Who should the remittance be payable to?
The form directs you to make the remittance payable to the Delaware Division of Revenue and mail it with the completed form.