The first function of the RFOs is that of a register, which, by virtue of its electronic nature, requires the digitisation of documents submitted by persons interested in paper. In accordance with Article 16 of Law 39/2015 of 1 October, the documents addressed to the Public Administrations may be submitted:

• In the electronic register of the Administration or Agency to which they are addressed.
• In the post office, in the manner prescribed.
• In the diplomatic representations or consular offices of Spain abroad.
• In the registers assistance offices.
• In any other case which lays down the provisions in force.

Documents submitted in person to the Public Administrations shall be digitised by the OAMR in which they have been submitted for incorporation into the electronic administrative file, the originals being returned to the person concerned, without prejudice to those cases where the regulations determine the custody by the Administration of the documents submitted, or the presentation of objects or documents in a specific medium not susceptible to digitisation is mandatory.