Period Covered

File the 2025 return for:

1. Calendar year 2025;
2. Short tax years beginning and ending in 2025; or
3. Short tax years beginning and ending in 2026, if the 2026 Form 1066 isn’t available by the time the REMIC is required to file its 2026 return. Even though the REMIC is filing the 2026 tax return on a 2025 Form 1066, any tax law changes effective after December 31, 2025, have to be applied on the tax return.

If you need more time to file Form 1066, file Form 7004, Application for Automatic Extension of Time To File Certain Business Income Tax, Information, and Other Returns, to request an automatic extension. You must file Form 7004 by the regular due date of Form 1066.