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Medium risk
020 3504 6210
AI Summary
Based on 2 community reports
Calls from this London number (020 3504 6210) on the Core Telecom network have been described by two users as suspicious. One report says it felt like a scam and involved silent calls to check if the line is active. The other notes a missed call with no message, described as suspected spam. With a spam score of 54/100, caution is warranted. If you don’t recognise the number, let it go to voicemail and block it. Do not share personal or banking details with unfamiliar callers.
Written automatically by AI from the community reports on this page. It does not set the spam score, and it can make mistakes, so read the reports below as well.
2 moderated reports
Every report is checked before it is published and counted towards the score. How moderation works
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
2 totalSubmitted by users and shown as written, so wording and spelling are their own. Each report is checked before it appears.
Felt like a scam i have had this number call me a fair few times now and because I don't recognise the number I don't answer now I did however answer it a couple of times early on and it was a silent call, I believe to check to see if it is a live number for scammers to confirm a target.
Called but left no message, suspected spam
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How this page was checked
This page is generated dynamically from community reports and lookup activity, and changes as new reports arrive. The risk score is based on community reports about calls and texts from this displayed number. It is not based on official records of who owns the number.
- Reports moderated by
- CallerCheck Moderation Team
- Safety guidance reviewed by
- CallerCheck Editorial Team
- AI summary
- Generated from approved community reports only
- Last report received
- 27 Aug 2026
- Last reviewed
- 27 Aug 2026
- AI summary last generated
- 21 Sep 2026
- Last materially updated
- 21 Sep 2026
What do these dates mean?
Report and lookup dates come from user activity. Review dates show when CallerCheck last checked the page. We use “last materially updated” only for meaningful page changes, not cosmetic changes.
- First seen:
- when this number first appeared on CallerCheck, through its first lookup or report.
- Last report received:
- the most recent approved community report for this number.
- Last lookup:
- the most recent time a user searched for this number.
- AI summary last generated:
- when the AI summary on this page was last rewritten from the approved community reports.
- Last reviewed:
- the most recent human moderation or editorial review, where available.
- Last materially updated:
- the most recent meaningful change to this page, such as a new report or a change to its score.
Sources and safety guidance
- Community reports about this number, screened before they are published or counted. How moderation works
- Ofcom numbering allocation data for the network this range belongs to
- Safety guidance aligned with UK scam-reporting advice, such as Report Fraud (formerly Action Fraud) guidance, forwarding spam texts to 7726, and the 159 banking helpline where relevant. Where to report a nuisance call
Important limits
Caller ID can be spoofed, so a high risk rating means people have reported suspicious activity involving this displayed number. It does not prove that the registered owner of the number made the call or text. Community reports describe individual experiences and are not official confirmation of a scam. How caller ID spoofing works.
Own or manage this number? If this number belongs to you or your organisation, you can claim or dispute this profile. We review claims, check supporting information, and may update the page if reports appear to involve spoofing, mistaken identity, or outdated information. Claim or dispute this number
About 020 3504 6210
What type of number is 020 3504 6210?
The phone number 020 3504 6210 (also written as +44 20 3504 6210) 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 3504 6210 safe to answer?
Based on 2 community reports, this number has received mixed reports from our community. The current risk score is 46% .
Be cautious when answering calls from this number. Verify the caller's identity before sharing any information.
What this data can and cannot tell you
The reports on this page come from members of the public about calls and texts that showed this number. Caller ID can be spoofed, so the person contacting you may not be the genuine holder of the number, and a legitimate number can be misused. Before paying anything or acting on a message, check the claim with the organisation involved using contact details from its official website or letters, never the ones in the message itself.
More on nuisance calls
Safety score
2 reportsHow this score was worked out
Each report rates the number as safe, unknown, suspicious or spam. The score combines those ratings, giving more weight to clear scams, and each person counts once. A number only reaches high risk once several people have independently reported it. Scores of 70% and above count as high risk, 40% to 69% as medium, and below 40% as low; a low-risk number reads Maybe Safe once someone reports it as safe. More about spam scores
Why this number is rated Medium Risk
This number is rated Medium Risk because community reports are mixed: 1 of 2 describe spam or suspicious activity, while 1 describe a legitimate or unknown call.
Ratings reflect screened community reports, not official records. How the spam score works.
Confidence: Medium
Based on 2 community reports. Confidence describes how much report evidence sits behind this page, and is separate from the spam score.
Caller ID can be spoofed, so reports may describe misuse of the displayed number rather than the registered number owner.
Details
- Tel Number
- 020 3504 6210
- Country
- 🇬🇧 United Kingdom
- Network
- Core Telecom
- Area
- London
- Type
- Geographic
- Coverage
- London and the surrounding area
- Cost to call
- Standard landline rate
- First Seen
- 24 Aug 2026
Network shows the operator this number range is allocated to, which is public information from Ofcom. The caller may be on a different network if the number was moved or spoofed. First Seen is the date this number first appeared on CallerCheck.
What people say about CallerCheck
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“Giving other people the heads up about scam calls from so called bank security !!”
Call Types
Breakdown of reported call reasons. Larger segments and bars represent a bigger share of reports.
Location
London, United Kingdom
This number originates from the London area code region. The map shows the general geographic area, not an exact location.
Protection Guides
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We review claims carefully and may keep warnings visible where community reports still indicate risk.