Calls from (020) 3644 XXXX — London
Block (020) 3644 XXXX is allocated by Ofcom to Virgin Media, on the London exchange (allocated 2012).
(020) 3644 XXXX is a number block in London, an area with a population of approximately 9,540,000. Standard landlines in this area use the format 020 3644 1234, with the first part being the dialling code and the rest being the local number.
This block — (020) 3644 XXXX — was allocated by Ofcom to Virgin Media in 2012. Virgin Media either operates the numbers directly or sub-allocates them to resellers and downstream carriers, which is why a single (020) 3644 XXXX prefix can be used by many different organisations. You can verify any allocation against Ofcom's National Telephone Numbering Plan, which is updated weekly.
Numbers in blocks like (020) 3644 XXXX are sometimes spoofed by overseas call-centres using VoIP. Spoofing makes a foreign call appear to come from a UK landline — including the area code where you live. If you don't recognise the number and the caller asks for any personal data, hang up and call the organisation back on a number you know is genuine.
If a (020) 3644 XXXX number called you and you're not sure who it was, the safest steps are: don't return the call until you've verified it (search the full number online first), don't share personal or financial details, and register the number with the Telephone Preference Service (TPS) if it's a marketing call. Persistent unwanted calls can be reported to Ofcom and the ICO. To block a specific number on most UK mobiles and landlines, you can also enable network-level call screening through your provider.
FAQs about (020) 3644 XXXX
Is (020) 3644 XXXX a real UK phone number?
Yes. (020) 3644 XXXX is part of an Ofcom-allocated UK number block — any number starting with that prefix is a real, dialable UK number assigned by Ofcom to Virgin Media for use on the UK public telephone network.
Who owns the (020) 3644 XXXX number block?
(020) 3644 XXXX is currently allocated to Virgin Media in Ofcom's National Telephone Numbering Plan. The allocated carrier may operate the numbers directly or sub-allocate them to downstream resellers — both arrangements are normal under UK telecoms rules.
Where is a (020) 3644 XXXX number based?
(020) 3644 XXXX is associated with London. UK geographic numbers historically indicated the location of the line, although VoIP services and number-portability rules mean a (020) 3644 XXXX number can technically be used anywhere a CP routes it. For most UK landlines the geographic match still holds.
How do I block calls from (020) 3644 XXXX?
On most UK smartphones, open the recent-calls list, tap the number, and choose 'Block this caller'. UK landlines from BT, Sky, TalkTalk and Virgin Media include free 'BT Call Protect'-style screening you can enable in your provider's app. You can also register your number with the Telephone Preference Service (TPS) at tpsonline.org.uk to opt out of legitimate UK marketing calls.
Other blocks in (020)
Try a different block within the same UK area code:
