What is Ofcom investigating about scam calls?
Ofcom has opened two investigations into how phone numbers are handed out and monitored, and the point of both is to cut down on scam calls. On 24 September 2026 the regulator opened cases into Vonage Business Limited and Voxbone SA, which trades as Bandwidth, over the possible misuse of phone numbers, including to carry out scams.
Your phone isn’t the thing under the microscope. The firms that supply numbers to businesses are. Still, it is the sort of story that explains why your mobile rings at teatime with a number you don’t know, so it’s worth five minutes of your time.
Ofcom says it is looking at whether each firm met General Conditions B1.6, B1.8 and B1.9(c), the rules on making sure allocated numbers are used effectively and efficiently and that the customers using them follow the numbering rules. The two cases are open, with references CW/01355/07/26 and CW/01357/09/26, and Ofcom says it will gather more information and publish an update in due course.
Key takeaways
- Ofcom opened investigations into two number suppliers on 24 September 2026.
- It has not said either firm broke the rules, and there are no findings yet.
- Scam calls go to Action Fraud, or Police Scotland on 101. The free 7726 service is for texts, though some networks also take call reports that way.
- Your phone’s built in call screening and blocking tools take a minute to switch on.
Why do scam calls come from real UK numbers?
Scammers need working numbers to reach you, and numbers come from phone companies. Ofcom expects those companies to take reasonably practicable steps to make sure the businesses they supply follow the numbering rules, so scammers can’t get hold of valid numbers in the first place.
That is the heart of both cases. Ofcom has said it will look at each firm’s monitoring and its risk based due diligence on customers. If those checks are thin, it is easier for the wrong sort of customer to get a number and start dialling.
This investigation sits inside Ofcom’s enforcement programme into phone and text scams, which opened on 1 February 2024 and was extended again in October 2025. It is one piece of a bigger clean up, not a one off.
Does the investigation mean those firms allowed scam calls?
No. Ofcom has reached no findings, and opening an investigation is not a verdict. It means Ofcom has concerns it wants to test.
That distinction matters, so we are keeping it plain. We’re not saying anyone did anything wrong. We are explaining what Ofcom has said it is looking at, and what you can do in the meantime.
What happens next is up to Ofcom, and investigations can take time. Don’t expect your phone to go quiet overnight. The practical steps below work today, and they cost nothing.
How can you protect yourself from scam calls on your mobile?
Most of us treat an unknown number as a coin toss. When Ofcom surveyed people in February 2025, a quarter, 26%, said they were likely or very likely to pick up a call from an unrecognised UK mobile number. That figure is more than a year old now, but it is the most recent Ofcom has published, and if you’ve ever let an unknown number ring out, you are in the majority.
Letting it ring is a fair move, but there are better ones. Based on Ofcom’s published advice on scam calls and texts:
- Use your phone’s tools. Most smartphones let you block specific numbers from your call log, and some can screen unknown callers so you see who is calling and why before you answer.
- Check your spam filters. Many phones have built in filters for calls and texts, and it’s worth checking they are switched on in your settings.
- Ask your network what it offers. Several run their own call filtering or caller protection services at no extra cost.
- Don’t click links in unexpected texts, even if they appear to come from someone you know.
- Don’t reply to texts from unknown senders, as it can confirm your number is active.
Doing nothing is the default setting for most phones. Five minutes in the settings app is the fix, and it won’t cost you anything. Ofcom has more detail on its page about how to protect yourself from scam calls, texts and messages.
One thing worth knowing: a blocked number buys you less than it looks like it does. Scammers change numbers constantly, and many fake the number they display, so blocking the one that just rang rarely stops the next call.
How do you report scam calls?
Reporting is free, but calls and texts go to different places, and it is easy to mix them up.
For a scam text, forward it to 7726. Ofcom says this is free of charge and alerts your provider, who can investigate and block the number.
For a scam call, Ofcom points you to Action Fraud, or to Police Scotland on 101 if you live in Scotland. Several networks also take call reports through 7726 on top of that: Vodafone, for one, tells customers to text the word CALL free to 7726 and then send the number when asked. O2 instead asks customers to ring 202. It is worth checking what your own network wants, because the route differs.
If you want to read more about the rules around spoofed numbers, see our piece on spoofed calls and Ofcom. Our guide to scam text messages and the new rules covers the text side, and a recycled mobile number can bring calls meant for someone else.
Do scam calls depend on your network or plan?
Scam calls can reach customers of any network, and no tariff makes you immune. What does differ is how your provider wants you to report a call, and what blocking or screening it includes, so that is worth a look whoever you are with.
If your current contract has drifted past its end date, or you simply fancy a look at what else is out there, a quick comparison is cheap in time. Just don’t expect a new deal to switch scam calls off.
Frequently asked questions about scam calls
- What is 7726 and is it free?
- 7726 is the free shortcode for reporting scam texts. Ofcom says forwarding a suspicious text to 7726 is free of charge and alerts your provider, who can investigate and block the number.
- How do I report a scam call?
- Ofcom points you to Action Fraud, or Police Scotland on 101 in Scotland. Some networks also accept call reports through 7726. Vodafone, for example, asks you to text the word CALL free to 7726 and then send the number. O2 asks you to ring 202 instead, so check what your own network wants.
- Has Ofcom found that Vonage or Voxbone allowed scam calls?
- No. Ofcom opened the two investigations on 24 September 2026 and has reached no findings. Opening a case means Ofcom has concerns it wants to test, not that a rule has been broken.
- Can I block scam calls on my phone?
- Most smartphones let you block specific numbers from your call log, and some can screen unknown callers or filter suspected spam calls automatically. Check the settings on your handset. Blocking helps, but scammers change and fake numbers often, so it is not a complete fix.
Sources
- Ofcom, investigation into Vonage Business Limited: the 24 September 2026 opening date, the General Conditions in scope and case reference CW/01355/07/26.
- Ofcom, investigation into Voxbone SA: the same opening date, the company’s trading name and case reference CW/01357/09/26.
- Ofcom, enforcement programme into phone and text scams: the programme’s 1 February 2024 opening and its extension.
- Ofcom, cracking down on scam calls from abroad: the 26% of people likely to answer an unrecognised UK mobile number, from February 2025 research.
- Ofcom, how to protect yourself from scam calls, texts and messages: 7726 being free for texts, the Action Fraud and Police Scotland routes for calls, and the blocking and filtering advice.
- Vodafone, nuisance calls and texts: the text CALL to 7726 route for reporting a call on that network.
Checked 1 October 2026.
