Frequently asked questions
Common questions about WhoCalledLookup, Ofcom range data, AI lookup accuracy, UK number validation and call safety.
This page is a single-screen reference for the questions we field most often. It covers four practical clusters: the identification workflow (how to actually find out who called you from a UK number, what UK law allows and forbids, why Range Holder data is not the same as live-carrier data); the number-family glossary (what 0300 / 0345 / 0808 / 070 actually cost in 2026 and what they are typically used for); the scam-safety cluster (how to tell whether an unknown call is a scam, where to report fraud, how to block repeat offenders); and the privacy and data answers (what we log, what we don’t, how the AI internet check is sourced and refreshed). The answers are written to be useful in their own right; if you want the long-form treatment of a specific question, follow the link inside the answer through to the dedicated guide.
If you can’t find your question below, the per-number reverse lookup on the homepage is usually the fastest route to a concrete answer — it returns the Ofcom Range Holder, the line type, and the live AI internet check summary in seconds. The guides under /blog cover the same ground at greater depth for readers who want the underlying rules and citations.
Who called me - how do I find out from a UK number?
Paste the number into the form at the top of this site. We return the Ofcom Range Holder, the line type and a live AI internet check that summarises any public reports about the exact number. Free, no signup, in seconds.
Whose number is this - can I look it up in the UK for free?
Yes for the type of line, the originally allocated provider (Range Holder) and any public reports. UK GDPR + DPA 2018 prohibit publishing the holder's name and address - so no public site can legally give you that, and any 'background check' service that promises to is either fabricating or scraping illegal data.
Is there a free UK reverse phone lookup with no signup?
Yes - WhoCalledLookup is free, no account, no card, no premium tier. Several other UK sites charge per result for substantially the same data; you should not need to pay.
How does WhoCalledLookup know who called me?
Two sources combined on a single page. (1) The official Ofcom Numbering Data, which lists the Range Holder for every allocated UK number block - refreshed weekly. (2) A live AI internet check that searches forums, scam-reporting databases and business directories for public reports about the exact number.
How fresh is the Ofcom range data?
We re-ingest from Ofcom every Wednesday, the day after Ofcom publishes the weekly numbering-data feed. The current snapshot date appears on every result page.
Why does the Range Holder differ from the network on caller ID?
The Range Holder is the original Ofcom allocation. Once a number is in service, the customer can port it to a different network - Ofcom does not publish current carrier data, and caller ID may show the porting carrier or be spoofed entirely.
Is 0345 free to call?
Effectively yes - 0345 calls cost the same as a 01/02 landline call and are included in inclusive minute bundles on every major UK mobile network in 2026. See our dedicated 0345 explainer.
What does 0808 cost?
Nothing - 0808 numbers are free to call from every UK landline and mobile, since the 2015 'UK Calling' rules. The receiving organisation pays the wholesale routing fee.
Is 0333 a premium rate number?
No. 0333 is a UK-rate non-geographic prefix regulated by Ofcom as standard rate. Calls cost the same as a 01/02 landline call and are included in mobile inclusive minutes. Premium rate in the UK starts with 09.
Are 070 numbers safe?
Treat them with caution. 070 is personal-numbering, not mobile - calls can cost up to 50p per minute, and 070 is heavily abused for one-ring 'wangiri' callback scams. Always identify before dialling back.
How do I check if a UK phone number is valid?
Three checks: format (10-11 digits with a known UK prefix); type (the prefix tells you landline / mobile / freephone / etc.); currency (paste it into our checker to confirm it is in the latest Ofcom Numbering Data). For developers, libphonenumber-js handles all three.
What is the E.164 format for a UK phone number?
+44 followed by the national number with the leading 0 stripped. So 020 7946 0000 becomes +442079460000. UK E.164 is typically 13 characters. See our UK phone number format guide for the full spec.
Is there a free UK phone number checker app?
WhoCalledLookup is a Progressive Web App - install it from Chrome or Safari with Add to Home Screen for an app-like experience without going through an app store. Free, no signup, no permissions to your contacts.
Is this number a scam - how do I tell?
Look it up here. If the Ofcom status is anything other than Allocated (Recovered, Free, Reserved, Protected) the call should not be ringing. If the line type does not match the caller's claim (e.g. 'bank' from a 070), it is a scam by definition. Universal red flags: urgency, one-time codes, requests for remote access, requests to move money to a 'safe account'.
Where do I report a UK scam call?
Action Fraud (actionfraud.police.uk or 0300 123 2040) for fraud reports. Forward suspicious texts to 7726 (free). Complain to Ofcom (ofcom.org.uk/complaints) for silent calls or repeated cold calls. If you gave any account details, dial 159 to reach your bank's fraud team safely.
How do I block UK spam calls?
Three layers: register on the TPS, turn on your network's free anti-fraud filter (every major UK network has one), and enable Silence Unknown Callers on iOS / Call Screen on Android. See our dedicated guide for the network-by-network instructions.
Do you store my phone number or my IP address?
We log lookups for analytics and rate limiting, but we store only a salted SHA-256 hash of the IP - never the raw IP. We do not sell data.
Can the AI scam score be wrong?
Yes. AI summaries reflect what is publicly findable on the web at the time of the lookup. New scam campaigns may not yet have public reports; legitimate businesses may have a few outdated negative reports. Always verify before acting.
Why is the AI score 0/10 even though I am sure this is a scam?
The AI may not have found public reports yet. Use the Refresh button on the result page to re-run the check. If you have evidence of fraud, please report to Action Fraud (0300 123 2040).
Can I look up non-UK numbers?
WhoCalledLookup currently only covers UK numbers (+44). Multi-country support is on the roadmap.
How do I find out who called me from a withheld or No Caller ID number?
You can't, directly — withheld numbers strip the CLI before it reaches your handset, so there are no digits to look up. Options: enable Silence Unknown Callers (iOS) or Call Screen (Android) to send unknown CLIs to voicemail automatically; use your network's anonymous-call-reject feature (1471 then 3 to query the last call, 14258 to reject withheld calls on BT lines); and report persistent harassment to Ofcom and to the police if it continues.
What does it mean if a number shows 'Recovered' or 'Quarantined' status?
Those are Ofcom allocation lifecycle states. 'Recovered' means the block was previously assigned but has been returned to Ofcom — usually because the holder ceased to use it. 'Quarantined' means the block was recently freed and is being held aside for a minimum period before being re-issued, to give time for stale CLIs to age out. Calls genuinely originating from a recovered or quarantined block should not be possible from a UK carrier; receiving one strongly suggests the CLI is spoofed.
Why does the same number sometimes return a different AI summary?
The AI internet check searches the live public web at the time of the lookup, then caches the result for 30 days. If new forum posts, scam reports or business directory entries appear within that 30-day window, the cached summary will not reflect them — but if the cache has expired the next lookup will pick up the new material. You can force a refresh from the result page if you have evidence the cached summary is stale.
Can a UK landline number really originate from outside the UK?
Yes, when CLI spoofing is involved. The wholesale network signalling that carries caller ID across UK carriers is trust-based — the originating carrier asserts the CLI and downstream carriers display it. VoIP gateways outside the UK can present a UK-format CLI, which is how many overseas scam operations look domestic to the recipient. The Range Holder data on this site reflects who Ofcom allocated the block to; it does not prove the live call actually originated from a UK exchange.
Is WhoCalledLookup GDPR-compliant?
Yes. We only process phone numbers (not personal identifiers tied to a named individual), and the only personal-data-adjacent identifier we touch is the visitor's IP address, which is salted-and-hashed for rate limiting and analytics rather than stored in raw form. We are the data controller for those hashed analytics records under UK GDPR and the Data Protection Act 2018; the lawful basis is legitimate interest in operating the service. No personal data is shared with third parties; no profiling decisions are taken; visitors can request access or erasure of any data we hold via the contact route on the About page.
How do I add the WhoCalledLookup app to my phone home screen?
On iPhone or iPad: open the site in Safari, tap the Share button, then 'Add to Home Screen'. On Android: open the site in Chrome, tap the three-dot menu, then 'Add to Home screen' or 'Install app'. The site behaves as a Progressive Web App once installed — it gets its own icon, a full-screen mode without the browser chrome, and a short offline cache for the homepage and previously-viewed lookups. No app store account needed.