eIDAS works, just not everyone knows it. The story of a certain e-signature.

Polish qualified signature and European law versus a wall of ignorance on the Spanish side. A customer tried to sign a document, but was told „you must have a Spanish signature.” We look at why this is illegal and how to respond.
eIDAS works, just not everyone knows it. The story of a certain e-signature
3-minute read Updated: August 18, 2026

Polish qualified signature, Spanish wall

Our customer stories aren't just stories - they're real-life experiences through which we observe what can really go wrong. We recently received a call from a client who had a qualified electronic signature issued in Poland and encountered a problem using it in another EU country. When trying to sign a document in the Spanish online system, our client was told: „you must have a Spanish signature issued by a Spanish operator”.”. Sound absurd? And rightly so - because it contradicts EU law.

What does the eIDAS law say?

eIDAS regulation (No. 910/2014) clearly states:

  • Qualified signature issued in one EU country is automatically recognized In all other member states. 
  • It has the same legal force as a handwritten signature - It cannot be denied any form or legal effectiveness.
  • No country can require a “better,” “national” qualified signature or impose additional requirements above those of the EU.

So why did the Spanish platform reject the Polish signature?

Possible reasons:

  1. Ignorance eIDAS - those operating the system may not have been aware of the law.
  2. Language or technical barrier - Perhaps there was a lack of support for the Polish certificate in a particular system (although this is not allowed), or it was a matter of simple ignorance of the language.
  3. Bad will or attempt to generate additional costs - Suggesting the need to purchase a new signature from a Spanish operator

     

Such action is contrary to the principle of mutual recognition of qualified digital signatures.

What if another EU country rejects the Polish signature?

1. cite eIDAS
2. pay attention to “non-discrimination”
  • The effectiveness of a signature cannot be denied just because it is electronic, or comes from another EU country
3. upload screenshots + eIDAS excerpt
  • If the system erroneously signals a lack of support, it is worth sending technical proof - such as a connection to a European Trusted List Browser, where it says Certum/SimplySign as QTS .
4. ask for justification in writing
  • If they refused, ask for a formal response - then you can report the matter to the supervisory authorities (in Poland UODO or Spanish CNIL/INCIBE).

Summary - Your rights in a nutshell

Issue

Legal status

Qualified Polish signature

Automatically recognized in all EU countries

Equivalence

Has the force of law as a handwritten signature throughout the EU

Refusal to recognize it

It is a violation eIDAS, you can file an appeal

How to defend yourself?

Invoke Articles 24a and 25 of eIDAS + Trusted List Browser

 

Polish qualified signature CertumMini/SimplySign works legally and effectively on the territory of the the entire European Union - Without boundaries or additional conditions. With these arguments, you can defend your right to use the signature without problems.

Qualified signatures SimplySign and Certum Mini

If you have any concerns or questions, please contact us

+48 22 417 05 55

We'll answer your questions, find a time that works for you, and match you with an advisor at one of our locations throughout Poland.

You can also write an email from us [email protected]. 

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