Unwanted calls are more than just annoying—they can be dangerous. From aggressive telemarketers to sophisticated scammers, knowing how to block these calls is essential. This guide covers everything you need to know about blocking unwanted calls on any device in the UK. If you've received a suspicious call, learn to identify common UK phone scams and report them to Ofcom.
Block Calls on iPhone
1 Block from Recent Calls
- 1 Open the Phone app and tap Recents
- 2 Tap the ⓘ icon next to the number you want to block
- 3 Scroll down and tap Block this Caller
- 4 Confirm by tapping Block Contact
2 Silence Unknown Callers
This feature silences calls from numbers not in your contacts, recent outgoing calls, or Siri suggestions.
- 1 Go to Settings → Phone
- 2 Scroll down and tap Silence Unknown Callers
- 3 Toggle the switch On
Note: Silenced calls will still appear in your Recents and go to voicemail. This may cause you to miss legitimate calls from numbers not in your contacts.
3 View & Manage Blocked Numbers
- 1 Go to Settings → Phone → Blocked Contacts
- 2 Here you can see all blocked numbers and swipe left to unblock
Block Calls on Android
1 Using Google Phone App
Most Android phones use Google's Phone app, which has built-in spam protection.
- 1 Open the Phone app and go to Recents
- 2 Tap and hold the number you want to block
- 3 Select Block/report spam
- 4 Optionally check "Report call as spam" to help others
2 Enable Spam Protection
- 1 Open the Phone app
- 2 Tap the ⋮ menu and select Settings
- 3 Tap Caller ID & spam
- 4 Enable See caller and spam ID and Filter spam calls
3 Samsung Phones
Samsung has its own blocking features through Smart Call.
- 1 Open Phone → ⋮ → Settings
- 2 Tap Block numbers
- 3 Enable Block unknown/private numbers if desired
- 4 Add specific numbers to block manually
Block Calls on Landlines
BT Call Protect
BT's free service that automatically blocks nuisance calls.
- Dial *227 after an unwanted call to add to your block list
- Manage your list online at bt.com/callprotect
- Activate by calling 0800 389 2047 or via My BT
Sky Talk Shield
Sky's call screening service (free for Sky Talk customers).
- Callers must announce themselves before connecting
- Activate via My Sky account or call Sky
- Whitelist trusted numbers to skip screening
Physical Call Blockers
Hardware devices that connect to your phone line and block unwanted calls.
CPR Call Blocker
Pre-programmed with thousands of known scam numbers. One-button blocking.
BT Call Guardian
Screens calls and asks callers to identify themselves.
UK Mobile Network Features
EE
- Call Safe feature in the My EE app
- Free spam warnings on incoming calls
Vodafone
- Scam Call Shield - free for all customers
- Automatic blocking of known scam numbers
Three
- Block numbers via Three app or online
- Use phone's built-in blocking features
O2
- Call screening through My O2 app
- Network-level scam protection
Register with TPS
The Telephone Preference Service (TPS) is the UK's official "Do Not Call" register. It's free to register and legally requires UK companies to stop calling you for sales and marketing.
What TPS Does
- • Stops legitimate UK marketing calls
- • Covers mobiles and landlines
- • Takes effect within 28 days
- • Registration is permanent
What TPS Doesn't Do
- • Stop scam calls from criminals
- • Block overseas callers
- • Stop calls from companies you've given consent to
- • Block market research calls
How to Register
Call Blocking Apps
Truecaller
Identifies unknown callers using a massive global database. Blocks spam automatically.
- ✓ Caller ID for unknown numbers
- ✓ Automatic spam blocking
- ✓ Community-based reports
Hiya
Samsung's default caller ID app. Clean interface with reliable spam detection.
- ✓ Real-time spam alerts
- ✓ Reverse phone lookup
- ✓ No ads in free version
RoboKiller
Premium app that answers spam calls with funny bots to waste scammers' time.
- ✓ Answer bots waste scammer time
- ✓ SMS spam blocking
- ✓ Personal block list
Privacy Note: Most caller ID apps work by uploading contacts to their servers. Read privacy policies carefully before installing.
Quick Summary: Best Practices
Essential Steps
- 1. Register with TPS (free, takes 5 mins)
- 2. Enable your phone's built-in blocking
- 3. Activate your network's spam protection
- 4. Block individual numbers as they call
Remember
- • No solution blocks 100% of spam
- • Scammers constantly change numbers
- • Report spam to help others
- • Never engage with suspected scammers
Still Getting Suspicious Calls?
Even with blocking enabled, some calls may get through. Learn to recognise scam patterns and protect yourself: