ATCUD

ATCUD, the mandatory unique identifier on Portuguese invoices.

Definition

The ATCUD is an alphanumeric string printed on every fiscally relevant document in Portugal. It is formed by concatenating the series validation code — assigned by the Autoridade Tributária (AT) after the series is communicated in advance — with the document's sequential number, in the form "ValidationCode-SequentialNumber". Mandatory since 1 January 2023, it also appears inside the invoice's QR code.

Origin

Mandated by Portaria n.º 195/2020 and the series/ATCUD obligations of the Autoridade Tributária e Aduaneira (Portugal), linked to Decree-Law 28/2019.

Example in context

ATCUD: CSDF7T5H-35 — where CSDF7T5H is the series validation code and 35 the document's sequential number.

Related terms

• SAF-T (PT) — Portugal's fiscal audit file tied to invoicing.