Spain is changing the caller ID that sales and marketing calls must carry. From October 17, 2026, companies covered by the country’s new customer service law can only place commercial calls from 9-digit numbers that begin with 400, a range the government created so people can tell a sales call apart from everything else ringing their phone. Geographic, toll-free, and mobile numbers stop being valid origins for that traffic.
For an international business with prospects in Spain, the change reaches well past the caller ID field. A 400 number can only place calls, so nobody can ring it back, and it can never carry customer service. This guide covers:
- Spain Phone Number Regulation Changes
- Why Is Spain Introducing the 400 Range?
- What Should Businesses Calling Spain Do Now?
Key Takeaways
- Spain has reserved the 400 range of its national numbering plan for commercial calls, under a resolution published in the Boletín Oficial del Estado (BOE), Spain’s official gazette, on April 16, 2026.
- From October 17, 2026, companies within the scope of Law 10/2025 must place commercial calls from 400 numbers only.
- The numbers are outbound-only: they can’t receive calls and can’t be used for customer service.
- The rule targets commercial calls. Customer service and post-sale calls run on other number ranges.
- Businesses get 400 numbers through a telecom provider, because Spain’s National Markets and Competition Commission (CNMC) assigns them only to operators.
What are Spain 400 Numbers?
Spain 400 numbers are a new block of the national numbering plan with a single job: placing commercial calls. They use the same 9-digit length as other Spanish numbers, so a call from one appears as 400 followed by 6 digits, or +34 400 XXX XXX in international format.
Spain 400 numbers, defined: Spain 400 numbers are dedicated outbound phone numbers introduced for commercial calls. They can originate calls but cannot receive incoming calls, and they cannot be used for customer service.
Spain Phone Number Regulation Changes
The 400 range traces back to Law 10/2025 on customer service, dated December 26, 2025. Article 16.3 of that law requires phone-based customer service and commercial calling to each use their own dedicated number code. The numbering detail arrived in a resolution from Spain’s Secretary of State for Telecommunications and Digital Infrastructure, dated April 14, 2026, published in the BOE on April 16, and in force from April 17.
That resolution gave the CNMC, operators, and companies making commercial calls 6 months to bring the range fully into service. The CNMC opened an initial allocation window in which operators could request 400 numbers in blocks of 1,000. When the 6-month period closes on October 17, commercial calls can only go out from the 400 range, and no other numbering range may be used for them.
This replaces a looser arrangement. Under a February 2025 ministerial order against phone scams (Order TDF/149/2025), commercial calls could still come from short codes, geographic numbers, or 800 and 900 numbers. Those ranges remain available for customer service, but from October 17 they drop out as origins for covered commercial calls.
Which Calls Count as Commercial
The rule covers calls that promote or sell a product or service. Spanish lawmakers set that apart from 2 other kinds of business calling: customer service, meaning queries, complaints, and incidents raised by existing customers, and post-sale service. Those calls keep their own numbering under a separate resolution dated the same day, which points them to short codes, 800 and 900 numbers, and geographic numbers.
The 400 requirement applies to companies within the scope of Spain’s customer service law, whether they’re established in Spain or abroad. That covers providers of basic services in Spain, such as energy, water, transport, postal, telecom, and financial services. It also covers consumer-facing companies selling in Spain that employ at least 250 people, or exceed €50 million in annual turnover or €43 million on the balance sheet, measured alone or across a corporate group.
Companies outside that scope shouldn’t assume they’re unaffected. The resolution’s deadline clause is worded broadly, and the law directs operators to block calls showing signs of commercial traffic without the dedicated code. Consent rules also still apply: Spain’s General Telecommunications Law already bars unsolicited commercial calls to people who haven’t agreed to receive them, so the range governs how a lawful call identifies itself while consent decides whether the call can happen at all.
Key Rules Businesses Need to Know
The resolution sets out how 400 numbers behave on the network and what they can be used for. These are the conditions that shape day-to-day outbound operations:
- Commercial calls only – The range is reserved for commercial calls and can’t serve any other purpose.
- Outbound only – A 400 number can originate calls but can’t receive them, and operators are barred from connecting any call dialed to a 400 number.
- No customer service – Support, complaint handling, and other service traffic can’t run on a 400 number.
- End-user destinations – Calls from a 400 number can only reach numbers that identify end users: geographic, mobile, and nomadic voice numbers.
- Network-wide support – Every operator offering public telephone service must open the range on its network, and calls from it count as fixed-network calls for interconnection.
- Portability – Operators holding 400 numbers must allow them to be ported, so a number can stay with a business that changes providers.
- An opt-out for recipients – Operators may let their customers ask to stop receiving commercial calls from the 400 range altogether.
Taken together, these conditions push businesses to run outbound commercial traffic and inbound customer service traffic as 2 separate systems. No single number can do both jobs once the deadline passes.
Why is Spain Introducing the 400 Range?
Spain’s stated goal is clarity, both for the people receiving calls and for the authorities overseeing how numbers are used. The resolution’s preamble explains the reasoning in some detail, and it falls into 2 themes.
Make Sales Calls Easy to Recognize and Supervise
Until now, a commercial call could arrive from almost any kind of Spanish number, leaving people unsure whether they were picking up a sales pitch, a delivery update, or their bank. The resolution says that mix made it harder for recipients to identify the nature of a call and for complicated official supervision of public numbering resources.
A dedicated code addresses both problems. Someone who sees 400 on screen knows the call is commercial before answering, and the CNMC, which supervises compliance with the resolution, gains one clearly defined range to monitor. People who receive commercial calls from any other kind of number can file a complaint with the Telecommunications User Service Office (OAUT) or the CNMC.
Reduce Room for Fraud and Callback Confusion
The outbound-only design is deliberate. According to the preamble, Spain wanted to protect end users, lower the likelihood of fraudulent conduct, and stop the range from turning into a new channel where people return a missed call and end up confused or frustrated.
The rule also extends Spain’s wider push against phone scams. Since June 2025, operators have had to block calls from abroad that display a Spanish number, except for customers who are roaming. Moving commercial traffic into its own labeled range makes legitimate sales calls easier to trust and irregular ones easier to spot.
What Should Businesses Calling Spain Do Now?
With the deadline close, preparation comes down to a short sequence: find the affected calls, get the right numbers, configure them, separate them from support, and test.
Note: The steps below assume you’ve confirmed with counsel that your company falls within the rule’s scope.
1. Map Every Campaign That Calls Spanish Prospects
Start with an inventory of every workflow that places commercial calls to people in Spain. Outbound sales cadences and lead follow-up are the obvious ones, and the list also includes renewal and upsell campaigns, meeting-setting for account executives, and marketing calls placed by agencies or outsourced contact centers for your brand. If your Spanish outreach runs through a phone system for sales teams, its campaign settings are a good place to begin.
For each workflow, record the dialer or platform it uses, the caller ID it shows today, and whether its calls are commercial or service-related. A support follow-up on an open ticket stays on its current number, while a call pitching an upgrade to an existing customer may well count as commercial. Mixed scripts are where most of the judgment calls sit, so flag them for legal review.
2. Get Your 400 Numbers Through a Provider
Businesses can’t request 400 numbers from the CNMC directly, since the regulator assigns the range only to operators of publicly available telephone service. Your provider sources the numbers and activates them on your account, so the first conversation belongs with whoever carries your Spanish voice traffic.
Work out how many numbers you need before that conversation. Some companies use one 400 number per brand, while others split them by campaign or business unit so reporting and complaint handling stay tidy. Because 400 numbers are portable, the ones you choose now can move with you if you switch providers later.
3. Set Caller ID and Routing for Spanish Outbound Traffic
Once the numbers are live, they need to appear on every commercial call into Spain. That usually means updating outbound caller ID settings in your dialer, softphone, PBX, or CRM click-to-call integration, and writing campaign rules that assign the 400 number to Spanish destinations only.
How the call reaches Spain matters as much as the number it displays. Spanish operators already block calls originating abroad that present a Spanish number, so a 400 caller ID attached to a call routed in from another country risks being dropped. Your provider needs to carry those calls on a route that hands them to the Spanish network the number belongs to. Our overview of European caller ID rules explains why domestic numbers on international routes now face filtering across much of the region.
4. Keep Customer Service and Callback Numbers Separate
A 400 number can’t take a returned call, which changes how prospects reach you after a missed connection. Pair every Spanish campaign with a dedicated inbound line, such as a Spanish geographic number or a 900 toll-free number, and include it in voicemails, follow-up emails, and agent signatures.
Use that line only for receiving calls, and route it to the right place, whether that’s the rep who dialed or a central sales desk. Your customer service lines stay on the ranges Spain’s separate customer service rules allow, and none of them should place commercial calls after the deadline. Tag each number by purpose in your CRM so agents always pick the right one.
5. Test Calls and Track Issues
Place test calls from each 400 number to Spanish mobile and geographic numbers across the major networks, and check that the full number displays correctly. Confirm that the callback numbers in your voicemails and emails ring through, that your dialer can’t fall back to an old caller ID, and that no commercial call to Spain leaves your system without a 400 number attached.
After launch, track connection and answer rates by number. Recipients can ask their operator to block 400 commercial calls entirely, so a sudden drop on one list may reflect opted-out contacts more than a network fault. Spotting those patterns early gives your team time to adjust targeting and scripts.
Get Spain 400 Numbers With Global Call Forwarding
Global Call Forwarding is adding Spain 400 numbers for businesses that need commercial calling into Spain to keep running under the new rules. The numbers run on our Outbound Calling service, and our team sources and activates them, sets them as caller ID on your Spanish campaigns, and carries the calls over our network.
Spain 400 numbers fit into the voice setup you already run. Agents can dial from the GCF Softphone or your PBX, or work inside the CRM and contact center tools you connect through our voice integrations, while Spanish inbound numbers handle callbacks and support. Call Detail Records and Custom Reports, both included with your plan, break down call volume and outcomes by number.
Talk to our team about Spain 400-number availability and setup. Call us at +1 (561) 908-6171 or chat with us online.
