Diia.Signature Abroad in 2026: What Is Legally Valid in the EU, How to Sign, Where the Limits Are

In short: Diia.Signature works from a smartphone in any country — physical presence in Ukraine is not required. For documents under Ukrainian jurisdiction it is a full qualified electronic signature (QES), equal to a handwritten one. For the EU there is a separate option — Diia.Signature-EU, which complies with the eIDAS regulation but has the status of an advanced signature (AdES), not a qualified one (QES), in EU countries. Important: from 2026, Diia.Signature can only be activated on a smartphone with NFC and a biometric document.

What is legally valid abroad — a short matrix

• In Ukraine: Diia.Signature (both UA and EU) is a QES, which by law is equated to a handwritten signature. Valid regardless of where you are physically located.
• In EU countries: Diia.Signature-EU is recognized as an advanced electronic signature (AdES). The document legally binds the parties and is admissible as evidence in EU courts, but does not have the presumption of authenticity that a qualified signature (QES) provides.
• Latvia (since January 2026): the only state with full mutual recognition — Ukrainian QES from the EU Trusted List are equated there to a handwritten signature (amendments to the Latvian Law on Electronic Documents entered into force in January 2026).

Why in the EU it is AdES, not QES

Ukraine became the first country outside the EU to be added to the European Commission's Trusted List of third countries (TC AdES LOTL). This means that Ukrainian signatures are technically compatible with EU standards and can be verified by European validation services. The European Commission confirmed that Diia.Signature-EU complies with eIDAS.

However, since Ukraine is not an EU member, its qualified signatures receive in the EU the status of advanced (AdES) rather than qualified (QES). The practical difference: QES provides an automatic presumption of authenticity (the burden of proof falls on the party who contests it), whereas AdES does not, although the document remains legally binding and admissible in EU courts. Full mutual recognition is still being agreed with the European Commission and has not yet been established (except in Latvia).

How to activate Diia.Signature (step by step)

What you need in advance: a smartphone with NFC support and a biometric document — an ID card, a biometric international passport or a residence permit. Without NFC and without a biometric document, Diia.Signature cannot be activated from 2026.

1. Update the Diia app to the latest version.
2. Menu → Diia.Signature → activate Diia.Signature.
3. Scan the document number (QR/MRZ on the back of the ID card or on the page of the biometric passport).
4. Read the document via NFC — hold the phone to the document so the app reads the data from the chip.
5. Pass the photo verification (PhotoID — the app compares your photo with the document).
6. Create a 6-digit PIN code. After that, signing is done using only this code, without repeated NFC.

On platforms that support the feature, during signing you can choose the standard: Diia.Signature-UA (for Ukrainian documents) or Diia.Signature-EU (for documents in the EU). At the time of launch this is a beta feature, available on ID.GOV.UA and the electronic document management service "Vchasno"; the list of platforms is expanding.

EU signatures in Ukraine

The mirror side: since 1 January 2023, EU qualified electronic signatures (QES) have been recognized in Ukraine as fully compliant with the requirements of Ukrainian law and equated to a Ukrainian QES. Since 3 October 2024, this recognition has been in force on a permanent basis through the Trusted List mechanism — under Resolution of the Cabinet of Ministers of Ukraine of 1 October 2024 No. 1131. If your counterparty in the EU signed a document with their QES and you signed with a Ukrainian QES, in Ukraine such a document is recognized as equal to one signed by hand by both parties. The signature can be verified at czo.gov.ua/verify.

Limits: what Diia.Signature does NOT replace abroad

• Digital documents in Diia (ID card, international passport) are intended for use within Ukraine. To cross the border, board a plane, and for official identification abroad, a physical international passport is required — a digital copy does not replace it.
• QES status in the EU is not granted by Diia.Signature-EU (except in Latvia). If a specific procedure in the EU explicitly requires a QES with the presumption of authenticity, check whether the institution accepts AdES.
• NFC and a biometric document. Without a smartphone with NFC and without a biometric document, the signature cannot be activated — take this into account in advance.
• Platform support. The choice of UA/EU is available only where the platform has technically integrated Diia.Signature-EU.

What to do right now

1. Check that your phone has NFC and that Diia contains a biometric document — without this, activation will not go through.
2. Update Diia and activate Diia.Signature while you have access to a biometric document.
3. For deals with a counterparty in the EU, agree in advance which signature standard the platform accepts (UA or EU) and whether AdES is sufficient for them.
4. Keep your physical international passport valid — Diia's digital documents do not replace it abroad.