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Scam calls can be disruptive at best and financially devastating at worst, with criminals attempting to trick you into handing over money or personal information.
Unfortunately, the problem isn't going away. In fact, new figures from the Information Commissioner's Office (ICO) show that complaints about automated nuisance calls have reached a five-year high.
But there are ways to fight back. On supported Android phones, for example, you can use call screening to find out who's calling and why before deciding whether to answer. Meanwhile, iPhone users can screen or silence unknown callers and filter suspected spam calls.
Below, we explain how to keep scam calls at bay on your mobile and highlight some of the best call-blocking landline phones uncovered by our rigorous tests.
Jump to: Screen calls on iPhone | Screen calls on Android | Block calls on a landline
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According to new figures from the ICO, the regulator received 3,684 complaints about automated nuisance calls in September 2026, up from 1,374 in July. That's an increase of almost 170% in just two months.
Andy Curry, Head of Investigations at the ICO, warns that the figures are 'likely to be just the tip of the iceberg', as many calls go unreported. To help reduce unwanted calls, you can register for free with the Telephone Preference Service (TPS) or report nuisance calls directly to the ICO. However, registering with the TPS won't necessarily stop scammers who ignore the rules.
Apple's Call Screening feature can help protect you from scam calls by asking unknown callers to identify themselves and explain why they're calling before your mobile rings.
Call Screening was introduced with iOS 26. To check which version of iOS you're using, go to Settings > General > About. To install the latest available update, go to Settings > General > Software Update.
To screen or silence unknown numbers on your iPhone, try this:
Bear in mind that silencing unknown numbers could mean missing genuine calls, including those from delivery drivers, healthcare providers or businesses you've recently contacted. If you're expecting an important call, check your voicemail and recent calls regularly.
You can also keep calls from unknown numbers separate from your main call history. Go to Settings > Apps > Phone > Call Filtering and turn on Unknown Callers. Missed calls and voicemails from unsaved numbers will be moved to a separate list.
To block individual callers, open the Phone app, find the number in your recent calls and select Block Caller. To unblock someone, go to Settings > Privacy & Security > Blocked Contacts, tap Edit and select the contact you want to unblock.
See also: 10 things every smartphone owner should do to keep their data safe.
Most Android phones have built-in features to help protect you from scam calls, including spam detection and, on supported models, call screening that asks unknown callers why they're calling.
If you use the Phone by Google app, which comes pre-installed on many devices, you can check your spam protection settings by following these steps:
On Google Pixel phones, you can use a feature called Call Screen to check who's calling before you answer. When you receive a call, tap Screen call and Google's tool will ask the caller to identify themselves and explain why they're calling. You'll see a live transcript of what they say, so you can decide whether to answer or hang up.
Some Pixel phones can also screen calls automatically, without you needing to tap anything. To check if your phone supports this, open the Phone app and go to Settings > Spam and Call Screen (or Call Screen). If automatic screening is available, you'll see options to turn it on and adjust how it works.
Samsung Galaxy phones also offer call-screening features. On the Galaxy S26 series, for example, Call Screening can answer unknown calls, ask who's calling and why, then display the caller's response on screen.
Older compatible Galaxy phones offer Bixby Text Call, which lets you read what a caller says and reply using typed messages.
You can also block calls from specific numbers. Open the Phone app, find the number in your call history and select Block/report spam. To unblock a number, go to Phone > Settings > Blocked numbers.
While many scams now start online, phone calls remain a common tactic used by fraudsters. Having a landline phone with effective call-blocking features can help you avoid unwanted callers.
Thanks to our tests, we know the handset you use can make a difference. The best cordless phones have effective, easy-to-use call-blocking features that can help protect you and your loved ones from persistent nuisance callers and scammers.
Some of the best features we've seen include blocklists that can stop entire categories of numbers, settings that only allow calls from designated contacts and dedicated buttons that reject incoming calls while adding the number to a blocklist.
A phone with effective call blocking could be particularly useful if you're buying for an older or vulnerable friend or family member who regularly receives unwanted calls.
| Model | Which? test score | Call blocking | Ease of use | Sound quality |
|---|---|---|---|---|
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| 80% (Best Buy) | ||||
| 78% (Best Buy) |
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Phone scammers often use spoofing to disguise their number and appear to be calling from a trusted organisation, such as a bank, HMRC or the police. Their aim is to trick you into handing over money or personal information.
Scammers can also use AI voice cloning to imitate people you know or trust. By manipulating caller ID information, they can make calls from abroad appear to come from UK numbers. Remember that a familiar-looking number doesn't guarantee a genuine caller.
Since January 2025, Ofcom has required phone providers to block calls from abroad that falsely display UK landline numbers, with limited exceptions. BT reported blocking up to one million calls a day during its first month of implementing the measures.
'If you've received a suspicious call on your landline, report it to your phone provider. If you've lost money to a scam, report it through Report Fraud (formerly Action Fraud). In Scotland, you should contact Police Scotland on 101.
'It’s vital that we all report dodgy numbers, as this can help lead to the closure of scamming operations, along with the prosecution of individuals involved. Help to make scammers fear the consequences of calling you.'
Callum Pears, Which? cordless phones expert
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