Scam calls and spam texts

Getting lots of unwanted calls and texts is annoying and can be worrying if you don’t know where they’re coming from. Register your mobile number via TPS to reduce the number of unsolicited live sales and marketing calls from businesses. Just text TPS with your email address to 85095.

If you’re receiving calls 28 days after registering, raise a complaint with TPS. You can also send an email to nuisance@telefonica.com with your mobile number and the number(s) calling you and we’ll notify the regulators.

Identifying unknown phone numbers can help you determine whether a call is from a legitimate source or a potential nuisance. Organise your contacts with up-to-date names and numbers of everyone you expect to call. That includes companies in your life who may want to get in touch about services or appointments.

We recommend ignoring unidentifiable calls unless you’re expecting it within an allocated timeframe. They’ll usually leave a voicemail if it is important. Responding may lead to further nuisance calls. O2 customers who are on a Pay Monthly custom plan, SIM Only plan or are with O2 Business benefit from Brand ID and Call Defence to help see who’s calling.

Blocking unwanted numbers is an effective way to prevent repeated nuisance calls. Most smartphones have built-in features to block specific numbers. On iPhones, you can go to the "Phone" app, select the "i" icon next to the number, and choose "Block Caller." On Android devices, the process is similar, usually involving holding down the number and selecting "Block" from the options.

If you get a missed call from a number you don’t know, think twice before calling them back, as you might be charged for the call. Sometimes these numbers only ring for a short time to force you to call them back. You should report these calls to nuisance@telefonica.com.

If you're getting spam texts, you can forward them to 7726. If appropriate, we'll report it to the Information Commissioner's Office (ICO). If the calls and texts have resulted in any fraudulent activity, we may need to report the experience to Action Fraud.

We may occasionally contact you about promotions and services that may interest you. If you don't want to receive further information from us, read our Privacy Policy for more information or contact us and we'll take you off our lists.

Visit Ofcom, Which?, Action Fraud and ICO for further industry advice.

Unknown calls do not display a number and show “No Caller ID” or “Unknown Caller”, making it difficult to identify the caller. They can be from telemarketers, scammers, or automated systems. NHS medical calls are also anonymous, however, so confirm a time period to answer this call.

Missed calls can be telemarketers who may ring multiple numbers at once or an attempt to gather personal information. They often cut the call short, relying on the recipient's curiosity to call back and certain numbers can lead to premium rate charges.

These voicemails pretend to be trustworthy organisations or incentive you with financial compensation. Generally, the voice is robotic and urges immediate action such as calling a number or providing personal information.

These voicemails pretend to be trustworthy organisations or incentive you with financial compensation. Generally, the voice is robotic and urges immediate action such as calling a number or providing personal information.

Malicious, abusive, or threatening calls are a criminal offence. If the caller is making direct threats and you believe they are real and immediate, call 999. If you don’t think they’re immediate, you should call your local police station on 101. In both instances, the police will decide the course of action to take against the offender(s).

If the phone numbers are being withheld, the police may advise you to contact us, and we'll arrange to trace the calls. This information can then be sent to the police (and only the police). As well as speaking to our malicious calls team over the phone, you can email malicious@telefonica.com with the details.

If you want to change your mobile number, get in touch and we'll help you with this. If you need more advice, take a look at the Ofcom guide on how to deal with malicious calls.

Brand ID lets you know when a genuine business is calling by showing their name on your screen, while Call Defence checks phone numbers to let you know if a call might be a scam or spam. It’s up to you whether you answer, but remember you should always be wary when giving any personal information over the phone.

If you’re on a Pay Monthly custom plan, SIM Only plan or with O2 Business, you’ll automatically see Brand ID and Call Defence labelling. No action is required from you to turn them on, but if you’re using an iPhone, you need to be running iOS 18.​ You can find out more about how Brand ID and Call Defence work on our dedicated help page.

Phone numbers are susceptible to random dialling, but more frequent calls may result from data breaches or data sharing when signed up to websites and services. Whether you’re on social media or subscribed to an app, checking privacy policies will help you understand how your data may be used. In some cases, numbers can be sold to third parties.

Numbers are private but persistent calls can sometimes be identified. Phones may provide identifiers such as the city location, and you may be able to find documented lists of common nuisance and scam numbers. Reporting spam helps to ensure it’s investigated.

To block WhatsApp spam text messages, hold your finger on a chat and select block [number] in the options. Avoid unknown callers setting off your ringtone: Settings > Privacy > Calls > Silence unknown callers.

Ignore unfamiliar numbers as a preventative measure. Answering or declining a call indicates your number is active and bad actors may pursue further.

Avoid opening text messages where possible. Malicious activity such as ‘smishing’ typically require you to click on links to compromise security. But opening it lets them know you are receiving them, which could prompt more targeted attempts. iPhones and some Android smartphones allow you to see messages without opening them by holding down on the preview.

It’s better to be cautious. Someone you know will leave a voicemail if it is important. When expecting a call, arrange a specific day and time allocation. Save the phone details of business services you use – such as dentists and maintenance workers – so they are identifiable when contacting you about appointments or reminders.

Changing phone number should be a last resort as it only stops existing nuisance calls instead of preventing them in the future. You’ll also need to update your details on various records, accounts, and notify anyone who may need to contact you. Having a second phone number can help you screen unwanted calls – one for public or work use and another for friends and family.