Since September 15th, Spanish carriers are required to block any business SMS whose sender isn’t officially registered — and almost no business owner knows this exists yet
A hair salon sends a reminder text the day before every appointment. It’s been doing it for years, with the same booking software as always. On an ordinary Tuesday in September, three clients don’t show up. The owner assumes they forgot, that life gets in the way, that people are like that. None of them forgot. None of them got the text.
There was no outage, no software bug, no weak signal. The message simply never left the carrier’s network. Since September 15th, by law, it can’t.
We’re nine days into this rule actually being enforced, and the vast majority of small businesses that text their clients — appointments, confirmations, reminders — have no idea it exists.
What changed on September 15th
Spain’s telecom regulator, the CNMC, approved a new rule back in March that creates an official Sender Registry: a list of which business names are allowed to appear as the sender of an SMS, MMS or RCS message. The goal is to cut off smishing — the fake texts that impersonate a bank or a delivery company to steal your data through a fraudulent link.
The date this blocking became truly mandatory was originally set for June 7th, but it got pushed back to give carriers and providers more technical time to adapt. September 15th stopped being a date on a calendar and became a rule that actually applies: if a message’s alphanumeric sender — the name you see instead of a phone number — isn’t registered, the carrier has to block it. It doesn’t notify whoever sent it. It doesn’t bounce. It just disappears.
Let me translate that: why you probably haven’t registered yours
Almost no business sends its own texts directly. It’s the booking software, the CRM, the marketing platform, the dental clinic’s scheduling tool with built-in reminders that actually sends the message. That provider is the one who technically has to have registered the sender name — tied to your brand or trade name — with the CNMC, through its official online portal.
The catch is that the registration has to be confirmed by the company that owns the brand, not just the technical provider. If nobody’s done that paperwork on your behalf, or the provider left it half-finished, the message keeps getting sent from their end — and keeps getting blocked along the way, with neither you nor your provider seeing any notice about it.
When someone actually looks closely…
…they don’t find a problem with forgetful clients. They find a broken link at a spot nobody’s watching: the gap between “the software says it was sent” and “the client received it.” Before September 15th, that gap was almost always zero. Now it might not be, and the only way to know is to ask, not to assume.
Twenty years teach you a lot, and one of the things they teach is that almost no client-communication failure ever gets noticed as a technical failure. It gets noticed as a client who “doesn’t come around as much,” a booking that “slipped their mind,” trust that erodes without anyone quite knowing why.
What to do this week
Ask directly whoever manages your text messages — the booking software, the CRM, the marketing agency — whether the sender name they use for your messages is registered with the CNMC. If they don’t know, that answer is the answer. If your provider gives you delivery-rate data, compare September against August: a drop there is the clearest signal you’re going to get. Check any platform you use yourself for marketing texts too, not just the booking one. And if you confirm the sender isn’t registered, ask for it to be filed — it’s submitted through the CNMC’s official online portal, tied to your brand or trade name, with a digital certificate.
No carrier is going to warn you that your messages are getting lost. Neither will your provider, unless you ask first.
At Netteleco we’ve spent years watching a technical rule nobody explains well end up costing real money to businesses that had no reason to find out on their own. If you’d like us to check whether your texts are actually getting through, get in touch.
