On July 28, 2026, Portugal's tax authority (AT) published Ofício Circulado n.º 25120 — a new administrative circular that replaces a 33-year-old document (OC 33129/1993) and rewrites the rules for correcting invoices and adjusting VAT. The update adapts the AT's position to electronic invoicing and recent legislative changes.
The deadline to comply is December 31, 2026. After that, the transitional period ends and the new rules apply in full.
