400 numbers: which company calls you from each one
Since 17 October 2026, sales calls in Spain may only come from nine-digit numbers starting with 400. The prefix tells you the call is a sales call, not who is calling. This page lists the 400 numbers whose company has been published, with the source that says so and the day we checked it.
A number is listed only when the company's own website, or a press article reporting what the company said, attributes it to that company. We do not use spam-list comments or the holder of the number block: 400 numbers are allocated to operators in blocks of 1,000, and an operator can serve other companies. If a number is not here, we have not found such a source; it does not mean the number is suspicious.
| Number | Company | Sector | Source | Checked |
|---|---|---|---|---|
| 400 001 004 | Movistar (Telefónica) | Telecommunications | Xataka MóvilPress · | |
| 400 120 120 | DIGI | Telecommunications | DIGICompany website · | |
| 400 120 122 | DIGI | Telecommunications | DIGICompany website · | |
| 400 120 131 | DIGI | Telecommunications | DIGICompany website · | |
| 400 120 134 | DIGI | Telecommunications | DIGICompany website · | |
| 400 887 887 | Avatel | Telecommunications | Demócrata (Agencias)Press · | |
| 400 100 425 | CaixaBank Payments & Consumer | Financial services | CaixaBank Payments & ConsumerCompany website | |
| 400 410 172 | CaixaBank Payments & Consumer | Financial services | CaixaBank Payments & ConsumerCompany website |
A matching number does not prove who is calling
- The number on your screen can be spoofed. If you are asked for bank details, passwords or a payment, hang up and call the company yourself on its customer-service number.
- 400 numbers do not accept calls, so you cannot call them back. Customer service stays on the usual numbers (for example, Movistar's 1004).
- Companies may only call you to sell if you are a customer or have given consent. You can ask them to stop calling.
Did a 400 number that is not on the list call you?
Most companies do not publish their 400 numbers. None of the most searched 400 numbers on Cleverdialer on 26 October 2026 had a published company, which is why they are not listed here.
How to report an unknown 400 number
- Look it up on NoCall: every number has its own page, where you can report the call and see whether other people have reported it.
- If a company calls to sell when you are not a customer and never consented, ask it to stop with the right-to-object letter.
- A sales call that does not come from a 400 number breaks the rule: you can complain to the Telecommunications User Office (OAUT).
- If you know which company a 400 number belongs to and a public source says so, send us the link and we will review it.
More about the 400 prefix
Sources for the rule
- Resolución de 14 de abril de 2026, de la Secretaría de Estado de Telecomunicaciones e Infraestructuras Digitales (BOE núm. 93, de 16 de abril de 2026, BOE-A-2026-8409) · Boletín Oficial del Estado
- Las llamadas comerciales deberán usar el prefijo 400 (nota de prensa, 16 de abril de 2026) · Ministerio para la Transformación Digital y de la Función Pública
- Oficina de Atención al Usuario de Telecomunicaciones (OAUT) · Secretaría de Estado de Telecomunicaciones e Infraestructuras Digitales
- Lista Robinson: servicio de exclusión publicitaria · Lista Robinson
Which countries it covers
Spain. The 400 rule applies to sales calls you receive in Spain.
Reviewed by hand. Each row shows its source and the date we checked it.
Frequently asked questions
How do I know which company is calling me from a 400 number?
The number alone does not say: 400 numbers are allocated to operators, which share them among their customers. Some companies publish theirs, and those are the ones this page lists with their source. If yours is not here, look it up on NoCall to see whether other people have reported it.
Can I trust a call from a number on this list?
The number matches the one the company published, but the number on your screen can be spoofed. Do not give bank details or passwords over the phone: if in doubt, hang up and call the company yourself on its customer-service number.
Why is a well-known 400 number missing?
Because we have not found a source that says which company it belongs to: neither the company's website nor an article reporting what the company said. Spam-list comments are not enough.