Qualified electronic signatures in Bulgaria: an independent guide

A qualified electronic signature (QES) issued in Bulgaria is the same legal instrument as a QES issued anywhere else in the European Union. This guide explains, for foreign citizens and foreign companies, how the Bulgarian market works: which providers can issue a QES, card or cloud, what providers ask from a foreigner, and what Bulgarian e-services say about foreign signatures. Facts were checked on 28 October 2026.

esign.bg is an independent guide in Bulgarian. We are not a trust service provider and sell nothing. Most of our detailed guides are in Bulgarian; we link them below and say so.

The legal basis: eIDAS

Regulation (EU) No 910/2014 (eIDAS) sets the rules for the whole EU:

• A qualified electronic signature has the equivalent legal effect of a handwritten signature (Article 25(2)).
• A QES based on a qualified certificate issued in one Member State is recognised as a QES in all other Member States (Article 24a(1), added by the 2024 amendment).
• Where a Member State requires an advanced or qualified signature for an online public service, it must recognise qualified signatures in the reference formats (Article 27).

In practice this means a QES you already hold from a provider in Germany, Romania or Spain is legally a QES in Bulgaria too, and a Bulgarian QES is valid abroad. Whether a particular website technically accepts your signature is a separate question; see the section on e-services below.

Who issues qualified signatures in Bulgaria

Each Member State publishes a trusted list of its qualified trust service providers (Article 22). The Bulgarian list is kept by the Communications Regulation Commission (CRC). In list no. 64 of 1 June 2026, five companies have an active ("granted") service issuing qualified certificates for electronic signatures. In alphabetical order of brand:

The list also contains providers whose services have all been withdrawn; a certificate from them issued today would not be qualified. You can check any provider in the EU/EEA Trusted List Browser. Our Bulgarian summary of the list is here (in Bulgarian), and prices are in our provider comparison (in Bulgarian).

Card or cloud

A QES needs a qualified signature creation device. There are two kinds in Bulgaria:

• Smart card or USB token. The key sits on a card you hold and plug in with a reader. You install the provider's middleware; our software and drivers guide (in Bulgarian) covers Windows, macOS and Linux.
• Cloud (remote) signature. The key sits in a device the provider manages on your behalf, and you approve each signature in a mobile app. B-Trust, Evrotrust and InfoNotary offer this; we found no cloud product on StampIT's pages, and eDocs' website was not reachable on 28 October 2026. In the trusted list, InfoNotary's personal signature service is flagged both for keys on a device the holder keeps and for keys managed on the holder's behalf.

Some Bulgarian systems accept only a card signature. See cloud and mobile signatures (in Bulgarian) for the details.

What a foreigner needs to get one

We list only what the providers' own pages say:

• B-Trust publishes a section for foreign companies: documents issued in the country of registration (including a current company extract), a power of attorney if someone else collects the signature, and a copy of the ID when the signature is issued to a foreign citizen. The documents must be notarised, translated into Bulgarian by a sworn translator, and carry an apostille unless Bulgaria has a legal-assistance treaty with that country. Notarisation can also be done by a Bulgarian consul. B-Trust's power-of-attorney templates are also available in English.
• Evrotrust publishes a list of countries whose passports, ID cards or personal numbers its system supports. It includes most EU states and several non-EU countries. Its smart-card QES has a separate price for legal entities registered outside Bulgaria (250.00 EUR on 28 October 2026, against 81.80 EUR for Bulgarian ones).
• InfoNotary says additional documents may be required depending on the legal form, the country of registration and the type of certificate.

For StampIT and eDocs we found no page for foreign applicants. Ask the provider before you travel or pay.

A practical point: the personal identifier inside the certificate. The ETSI standard for certificate profiles lets the identifier be based on a national personal number ("PNO"), a national ID card ("IDC"), a passport ("PAS") or a tax number ("TIN"), followed by the country code. Bulgarian e-services usually look for a Bulgarian personal number (ЕГН) or a foreigner's number (ЛНЧ) there. Ask the provider which identifier your certificate will carry.

Using a foreign or Bulgarian QES with Bulgarian e-services

Official pages we read on 28 October 2026 say the following:

• National Revenue Agency (NRA). If your certificate has no identifier the portal recognises, the portal shows a request form after login. You fill in the identifier type and number, print the form, sign it by hand and take it to any NRA office; after the office confirms it you get access. Until then only the free services are available. Our Bulgarian guide: NRA login with a QES.
• Public procurement (CAIS EOP). The official FAQ requires a qualified signature for self-registration of an economic operator, recommends a "Signature Test" before work, and allows the ESPD to be signed outside the system and attached as a file. It does not address foreign signatures; ask the CAIS EOP help desk. Our Bulgarian guide: CAIS EOP and ESPD.
• Secure electronic delivery (ССЕВ). Login with a QES asks you to choose the provider of your signature; the help page does not say whether foreign providers are offered. See ССЕВ and egov.bg (in Bulgarian).

We did not find an official Bulgarian page that lists the foreign QES providers a portal accepts. If a portal rejects your signature, ask the institution in writing and mention Article 24a of eIDAS.

Check a signature

To see who signed a PDF or P7S file, when, and whether the issuer is on the Bulgarian trusted list, use our in-browser signature checker (interface in Bulgarian; the file is not uploaded). For signatures from other countries, use the European Commission's DSS demonstration validator, which reads all EU trusted lists. The providers' policy documents are described in trust service documents, and company signatures in signatures and seals for companies.