Scam/Fraud
2 months ago
said from O2 -
Community overview
Community rating:
Negative
7 user reports
First reported 21 May 2026
·
Last reported
2 months
ago
User Reports (7)
Scam/Fraud
2 months ago
Said from 02 replacing sim cars
Scam/Fraud
2 months ago
Said they were from O2 and they were replacing SIM cards
Unknown Caller
2 months ago
Stated as suspected spam so I didn't answer the call
Spam
3 months ago
Said she was calling from 02 clearly wasn't, otherwise she would have known my name and details, tried to say something was wrong with my Sim card! and that she would send a new one, where to? if she doesn't know who i am
Unknown Caller
3 months ago
Did not recognize number so didn't answer. No message left. Security software flagged it as suspected spam
Unknown Caller
3 months ago
Telephone call from 0203 3905 3820, figured it may be held by same people. It's 🚫 not a number I recognise so didn't answer. No message left.
Report this number
↑ Back to reportsHow to Block This Number
On iPhone
- Open the Phone app and go to Recents
- Find the number 020 3905 3821 and tap the info icon (i)
- Scroll down and tap Block this Caller
- Confirm by tapping Block Contact
On Android
- Open the Phone app and tap the 3-dot menu
- Go to Call history or Recents
- Long press on 020 3905 3821
- Select Block number or Block/report spam
On Landline Phones
Several options are available for UK landlines:
- BT Call Protect - free for BT customers
- TalkTalk CallSafe - free for TalkTalk customers
- Call blocking devices like CPR Call Blocker (available on Amazon)
Register with TPS (Telephone Preference Service)
The TPS is a free service for UK consumers that allows you to opt out of unsolicited sales and marketing calls.
Learn more about TPS registrationAbout this number
Number formats
- UK format: 020 3905 3821
- International: +44 20 3905 3821
Number details
- Number type: Landline
- Number range allocated to: Gamma Telecom Holdings Limited
- Area: London
- Area code: 020