Since the United Kingdom and Portugal are both signatories of the Convention of Hague of the 5th of October of 1961, known as the Convention of the Apostile, the consular authorities do not legalize documents

Each signatory country has a competent authority designated to affix the Apostile. Such entity in the United Kingdom is the ​Foreign and Commonwealth Office. In Portugal Procuradoria-Geral da República affixes Apostiles.​

British Documents

Portuguese Documents

Information relating only to the legalisation of certificates of civil status​

United Kingdom 
British certificates do not need to be legalized or translated into Portuguese;
 
European Union countries (EU28)
In the EU, certificates issued in a bilingual format (Regulation (EU) 2016/1191) do not need to be legalised;
 
Member countries of the Vienna Convention (of 8 September 1976)
No legalization or translation into Portuguese is required;
 
Member countries of the Hague Convention (of 5 October 1961)
Certificates must be legalised by The Hague Apostille;

Click here to see the list of countries and their conventions.

Any other country
You must consult the Portuguese Consular Network with jurisdiction over the territory issuing the certificate you wish to legalize and/or translate. 

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Translation of Civil Registration Certificates

​Foreign certificates must be translated into Portuguese, except for the following:

• British certificates;
• Certificates issued in the EU model 2016/1191;
• Multilingual certificates of the Vienna Convention;
• Certificates issued in English.

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