For the 2025 tax period, withholding agents must electronically submit the CU 2026 form to the Revenue Agency:
- by March 16, 2026 if relating to income from employment or occasional self-employment;
- by April 30, 2026 if relating to income from self-employment falling within the scope of regular artistic and professional activities;
- by November 2, 2026 (deadline for submitting form 770/2026) if relating exclusively to income that is exempt or cannot be declared using the pre-filled tax return.