How to register your SMS sender with the CNMC, step by step
· 4 min read
Since 15 September 2026, Spanish operators block SMS whose text sender
—the name that appears as the sender, such as MyClinic or MyShop— is not
registered in the CNMC Alias Registry in the name of its owner. It is not
a recommendation: it is Order TDF/558/2026, and the blocking is applied by the
network. From that date, an unregistered sender means messages that do not
arrive.
The good news: the procedure is a form on the CNMC's electronic office, it is done only once per brand, and if you send with SMSverifica we prepare it with you. Here is the complete process.
Before you start: what you need
- The alias you want to register: from 1 to 11 characters, letters and numbers (that is the technical limit of the SMS sender).
- Who the owner is: the brand is registered in the name of a tax ID. It can be your company, your sole-trader registration or your end customer's company.
- On what grounds you use that name: the CNMC asks for the link — your company name, your trade name, a registered trademark, an internet domain of your own, or the authorisation of the trademark owner.
- A digital certificate of the owner (or of their representative), to approve the application when the CNMC notifies it.
The form, field by field
The application is filed here: Alias Registry form — CNMC electronic office
- Alias: write the sender exactly as you want it to appear on your recipients' phones.
- Type: SMS/MMS.
- Owner: the tax details of the brand's owner (tax ID, company name).
- Provider (PRO): select ABARCANDO — we are a registered originating provider and we appear first in the list. This field states which platform is authorised to carry SMS with your brand: if you do not name your actual provider, your sendings will keep being blocked even if the alias is registered.
- Justification: choose the link (company name, trade name, registered
trademark, own domain or authorisation of the owner) and provide the data
that proves it — the trademark number and its office, the domain without
https://, or who authorises you and in what capacity.
Once the application is sent, the CNMC will notify the owner, who has 10 working days to approve it with their digital certificate. Without that final click the application lapses (silence means rejection), so it is worth warning whoever holds the certificate before filing anything.
When the Registry publishes the alias, there is nothing to touch at SMSverifica: our system downloads the Registry daily and your brand is enabled automatically in your sendings.
If you are a Spanish company or sole trader
The straightforward case: you yourself (or your advisor) file the form and approve it with your company or sole-trader digital certificate. From start to finish, recent experience is days, not months.
If you send with SMSverifica and would rather not wrestle with the electronic office, we can also handle it for you from your dashboard (the “Senders” section): we prepare the application with your tax details and all you have left is the approval with your certificate when the CNMC notifies you.
If you are a foreign company
Here is the small print almost nobody mentions: the approval requires a Spanish digital certificate, so a company with no presence in Spain needs a national representative to file and sign the application on its behalf — with a representation contract in between that sets out responsibilities, because whoever signs answers for the brand belonging to whoever claims it.
We offer that representation service to the platform's customers, with its contract and its safeguards. If that is your case, write to us and we will tell you the requirements and the documentation needed before signing anything.
And while the registration is being resolved?
Your sendings do not stop: SMSverifica customers send from day one with a generic platform sender already registered in the Registry, which passes the 15-09 cut-off with no procedure at all. As soon as your brand is published, your SMS start going out with it — without changing a line of your integration.
In summary
| Your case | What to do |
|---|---|
| Spanish company or sole trader | Electronic office form + approval with your certificate (or we handle it from your dashboard) |
| Your end customer's brand | The owner is them: their tax ID and their certificate (or their authorisation in your favour) |
| Foreign company | National representative with a contract — contact us |
| Not registered yet | You send anyway with the platform's registered generic sender |
The expensive mistake is waiting until September: registration takes days, the owner's approval has a deadline, and on 15-09 the network does not ask — it blocks.