020 3535 0520
Also shown as:
- 020 3535 0520
- +44 20 3535 0520
AI Summary
Based on 1 community report
This London number, routed through Gamma Telecom Holdings, has received a report about unsolicited calls regarding cavity wall insulation. With only a single report and no community voting yet, it's difficult to establish a clear pattern, though the spam score of 62/100 suggests some concern. Cavity wall insulation calls are commonly used in nuisance calling campaigns, where callers attempt to generate leads or push unwanted services. If you receive a call from this number and didn't request insulation information, it's likely a sales call rather than a legitimate enquiry from your provider. Consider blocking it if calls persist, and remember that genuine home improvement companies typically don't cold-call unsolicited.
1 verified report
Cumulative spam score based on all reports up to each month. Higher percentage means higher reported scam risk. Cumulative spam score based on all reports up to each week. Higher percentage means higher reported scam risk. Cumulative spam score based on all reports up to each day. Higher percentage means higher reported scam risk.
Most helpful reports
1 totalWanted to talk about my cavity wall insulation.
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About 020 3535 0520
What type of number is 020 3535 0520?
The phone number 020 3535 0520 (also written as +44 20 3535 0520) is a UK landline number originating from the London area in Greater London . Calls to this number are charged at standard UK landline rates, usually included in call packages.
Is 020 3535 0520 safe to answer?
Based on 1 community report, this number has received mixed reports from our community. The current risk score is 62% .
Be cautious when answering calls from this number. Verify the caller's identity before sharing any information.
More on nuisance calls
Safety Score
Details
- Tel Number
- 020 3535 0520
- Country
- 🇬🇧 United Kingdom
- Network
- Gamma Telecom Holdings
- Area
- London
- Type
- Geographic
- First Seen
- 25 Aug 2026
Protection Guides
Location
London, United Kingdom
This number originates from the London area code region. The map shows the general geographic area, not an exact location.
Call Types
Breakdown of reported call reasons. Larger segments and bars represent a bigger share of reports.
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