On October 17, 2026, Spain’s six-month period for making the 400 commercial-call range fully operational ends. The BOE resolution designates nine-digit numbers beginning with 400 for covered businesses’ outgoing commercial calls.
What Spain’s 400 prefix requires
The 400 range is for outgoing commercial calls. It cannot receive incoming calls or be used for customer service, and operators must not connect calls to 400 numbers. The resolution also allows operators to offer customers, on request, disconnection from the 400 commercial-call service.
Which businesses does Law 10/2025 cover?
Spain’s Law 10/2025 covers providers of specified basic services of public interest that operate in Spain, as well as relevant businesses that offer goods or services to consumers and meet at least one of the size or financial thresholds below.
| Statutory category | Qualifying condition |
| Specified basic services of public interest | The provider operates in Spain. |
| Consumer-facing businesses | At least 250 employees, annual turnover above €50 million, or an annual balance sheet above €43 million. Any one threshold qualifies. |
Two deadlines, two obligations
The October 17 deadline applies to the 400 numbering range. Law 10/2025 sets a separate 12-month period for businesses to adapt customer-service services, ending December 28, 2026. During customer service, a commercial offer is permitted only when it relates to resolving the customer’s query, complaint, or incident and provides an improvement.
