Article 27

If a Member State requires an advanced electronic signature to use an online service offered by, or on behalf of, a public sector body, that Member State shall recognise advanced electronic signatures, advanced electronic signatures based on a qualified certificate for electronic signatures, and qualified electronic signatures in at least the formats or using methods defined in the implementing acts referred to in paragraph 5.

If a Member State requires an advanced electronic signature based on a qualified certificate to use an online service offered by, or on behalf of, a public sector body, that Member State shall recognise advanced electronic signatures based on a qualified certificate and qualified electronic signatures in at least the formats or using methods defined in the implementing acts referred to in paragraph 5.

Member States shall not request for cross-border use in an online service offered by a public sector body an electronic signature at a higher security level than the qualified electronic signature.

The Commission may, by means of implementing acts, establish reference numbers of standards for advanced electronic signatures. Compliance with the requirements for advanced electronic signatures referred to in paragraphs 1 and 2 of this Article and in Article 26 shall be presumed when an advanced electronic signature meets those standards. Those implementing acts shall be adopted in accordance with the examination procedure referred to in Article 48(2).

By 18 September 2015 , and taking into account existing practices, standards and Union legal acts, the Commission shall, by means of implementing acts, define reference formats of advanced electronic signatures or reference methods where alternative formats are used. Those implementing acts shall be adopted in accordance with the examination procedure referred to in Article 48(2).