The Spanish government is introducing a standard identifier for advertising calls from 17 October 2026: commercial calls must then use numbers with the 400 prefix. This was announced by Óscar López, Minister for Digital Transformation and Public Administration. The aim is to make advertising and sales calls clearly identifiable before they are answered, and to curb unwanted and fraudulent contacts.
The requirement has been published in the Official State Gazette (BOE) and is being implemented by the State Secretariat for Telecommunications and Digital Infrastructures. It requires operators to block commercial calls that do not use the new numbering. This reserves a specific number range exclusively for telemarketing; ordinary private or business calls are not affected.
The measure is part of the government plan against telephone and SMS fraud launched in March 2025. Since its introduction, operators have blocked more than 300 million fraudulent calls and 26.6 million text messages, according to government figures. The approach combines network blocks against obvious attempts at deception with clear identification of commercial contacts to better protect consumers.
In the same context, López presented an interim assessment of helpline 017, “Tu ayuda en ciberseguridad”, run by the National Cybersecurity Institute (INCIBE). Between 1 January and 18 June 2026, 95,064 enquiries were handled – almost twice as many as in the same period the previous year and nearly as many as in the whole of 2024. The service helps members of the public with questions and incidents involving cybersecurity and digital scams.
By making the 400 prefix compulsory, the government aims to increase transparency around telephone contacts and make it easier to enforce existing consumer rights. The rule comes into force on 17 October 2026; from that date, companies making advertising or sales calls must be identifiable by their use of the 400 prefix. Network operators have announced that they will block calls made for commercial purposes that continue to come through without the required prefix.
Editor: Phillipe Schmidt-Araguin (Article created with AI assistance).