E-signatures in commercial contracts in Portugal

An electronic document satisfies the legal requirement to be concluded in written form when its content is capable of representation as a written declaration. Furthermore, when a qualified electronic signature certified by an accredited certifying body is affixed to the electronic document, the electronic document concerned will have the same full and complete probative power of a private document signed with a public notary office (meaning that it creates the presumption that: (i) the person who affixed the qualified electronic signature is the holder of such signature or a representative of the holder; (ii) the signature was affixed with the intention of signing the electronic document; and (iii) the electronic document did not change since the qualified electronic signature was affixed).

All other forms of electronic signature afixed on an electronic document (other than the qualified one) are deemed to be equivalent to an autograph signature affixed on a paper form document.

  • Real estate sale and purchase Agreements; 
  • Leasing Contracts;                                                                    
  • Contracts relating to corporate; pre-emption rights, re-purchase rights, purchase options and sell options; 
  • Licence and transfer rights, contracts on copyrights;  
  • Contracts on mortgages and pledges; 
  • Contracts on security deposits; 
  • Consumer Financing agreements;              
  • In general, all legal statements subject to public registry.

The written form may also be required by other Serbian laws (e.g. an agreement on the transfer of certain other types of intellectual property), and certain agreements must be notarised in accordance with the applicable relevant Serbian laws (e.g. agreement on sale and purchase of real estate).


4. Main and relevant court practices

Judgment of the Portuguese South Central Administrative Court, of 19 June 2019 (law case nº. 2226/18.1BELSB), on the obligation for electronic signatures to be qualified in the context of public procurement.

5. In which cases are documents only with wet ink signatures accepted?

In agreements where the form of public deed is required, for example in Real Estate purchase and sale agreements. 

6. List of the relevant national legislation

Decree Law nº. 290-D/99, of 2 August 1999, as amended and republished by:

  1. Decree Law nº. 62/2003, of 3 April 2003 (which made the regime established in Decree Law nº. 290-D/99 compatible with the European Union Electronic Signatures Directive (1999/93/EC));
  2. Decree Law nº. 165/2004, of 6 July 2004;
  3. Decree Law nº. 116-A/2006, of 16 June 2006; and
  4. Decree Law nº. 88/2009, of 9 April 2009 (“RJDEAD”).

1. Electronic document signed with qualified electronic signature (QES as defined in the eIDAS Regulation) and with a time stamp


2. Electronic document signed with qualified electronic signature (QES as defined in the eIDAS Regulation) without a time stamp


3. Electronic document signed with advanced electronic signature (AdES as defined in the eIDAS Regulation) and with a time stamp


4. Electronic document signed with advanced electronic signature (AdES as defined in the eIDAS Regulation) without a time stamp


5. Electronic document signed with advanced biometric signature


6. Electronic document signed with a simple, standard electronic signature (SES)


7. Scanned electronic version of the original paper-based document with handwritten signature sent as an attachment in ordinary e-mail without an electronic signature, but with standard e-mail signature panel

Yes (provided that the original paper-based document is not required for the purposes of the legal statement concerned). 

8. Legal statement sent as a text of an ordinary e-mail without an electronic signature, but with a standard e-mail signature panel


9. Legal statement sent in an SMS


10. Electronic document with a copy-pasted image of a handwritten signature, sent as an attachment of an ordinary e-mail

Yes (it is deemed a written legal statement, provided that the copy-pasted image of the handwritten signature is affixed on electronic documents issued in series/large scale).

11. Electronic document with the typed name of the signer and sent as an e-mail attachment


12. Electronic legal statement sent in a social-media message sending application (e.g. Messenger, Viber, LinkedIn, Facebook message, etc.)


13. Electronic legal statement sent in a chat application


14. Electronic document created on an electronic platform ensured by the other party requesting the legal statement (without an electronic signature) by another party whom the operator of the platform granted access 


15. Electronic document signed in DocuSign/Adobe Sign with a simple standard electronic signature (no QES or AdES)


16. Electronic document signed with a qualified electronic seal as defined in the eIDAS Regulation


17. Agreements accepted by the other party online, by ticking a checkbox or by clicking on a button ("click on agreements")

Yes (provided that the ticking/clicking on a button process fulfills the requirements for valid electronic signatures).  
Fernando Cruz Trinca
Fernando Cruz Trinca