Start with your phone's call log and built-in tools
The fastest way to identify an unknown caller is to check your phone's call history. Every smartphone keeps a record of incoming calls, including the number, date, and time. On an iPhone, open the Phone app and tap the Recents tab at the bottom. On Android, open the Phone app and tap the Recents or Call Log tab. You will see a list of all recent calls with phone numbers displayed.
If you see a number you do not recognize, your phone may already have identified it. iPhones running iOS 13 or newer show caller identification for some spam and business calls automatically. Android phones with Google's Call Screen feature (available on Pixel phones and some others) will label suspected spam calls. Look for a label like "Spam Risk" or a business name next to the number.
If your phone did not identify the caller, write down the full phone number including the area code. You will need this number for the next steps.
Key Takeaways
- Check your phone's call log first — iPhone uses the Phone app's Recents tab, Android uses the Phone app's Call Log tab.
- Reverse phone lookup websites like TrueCaller, WhitePages, and Spokeo search public records to match phone numbers to names and addresses.
- Google Search can identify a number if it belongs to a business, government office, or person with a public web presence.
- If the number called multiple times, it is likely a business or scammer rather than a personal contact.
- Never call back a number you do not recognize without first confirming what it is — scammers use fake caller ID.
Use reverse phone lookup websites
A reverse phone lookup searches a database of phone numbers to find the person or business associated with them. Several free and paid services offer this. TrueCaller is one of the most popular — download the app or visit truecaller.com, enter the phone number, and it will show you the name and type of caller (personal, business, or spam). The free version works for most lookups.
WhitePages (whitepages.com) and Spokeo (spokeo.com) are two other common options. Both let you enter a phone number and search their public records databases. WhitePages is free for basic searches. Spokeo charges a small fee for detailed reports but offers a free preview. These services pull from public records, business directories, and social media to match numbers to names.
Keep in mind that reverse lookup services work best for landlines and business numbers. Cell phone numbers are often not listed in public databases, so a lookup may return no result even if the number is real. If you get no match, the caller was likely calling from a personal cell phone.
Search the number on Google
Before paying for a lookup service, try searching the phone number directly in Google. Put the full number in quotes — for example, "(555) 123-4567" — and search. If the number belongs to a business, government office, hospital, or any organization with a web presence, Google will often show you the name and what the organization does.
This method also helps you spot scams. If you search the number and find forum posts or complaint websites saying it is a scam, you have your answer. Many people post about unwanted calls on sites like ScamWarner or the Federal Trade Commission's complaint database, so a quick search can save you time.
Google will not find personal cell phone numbers unless the person has published their number publicly online. But for any business or organization, a Google search is usually faster and free.
Check if it is a known scam number
If a number called you repeatedly or at odd hours, it is probably not a personal contact. Scammers and robocallers often use the same number across many calls. Search the number on ScamWarner (scamwarner.com) or the FTC's complaint database (reportfraud.ftc.gov) to see if others have reported it.
You can also check your phone's built-in spam filter. On iPhone, go to Settings > Phone > Silence Unknown Callers to automatically send unknown numbers to voicemail. On Android, open the Phone app, tap More (three dots), then Settings > Spam and Abuse to see if the number is flagged there.
If the number is flagged as spam by multiple sources, do not call it back. Scammers use fake caller ID to make their number look like it came from your bank, the IRS, or a utility company. Calling back confirms your number is active and can lead to more calls.
Ask your phone provider for help
If you have a landline or a phone plan through a major carrier like Verizon, AT&T, or T-Mobile, you can contact your provider's customer service and ask them to identify a number. Providers have access to more detailed records than public databases and can sometimes tell you who owns a number even if it is not listed publicly.
This is most useful if the call came from a business or organization. Personal cell phone numbers are protected by privacy laws, and providers cannot always release that information. But if the number belongs to a company, your provider may be able to tell you the business name and location.
Call your provider's customer service number (usually on your bill) and explain that you received a call from an unknown number. Have the phone number and the date and time of the call ready. They may be able to help you identify it, though response times vary.
What to do if you still cannot identify the caller
If none of these methods work, the number likely belongs to a personal cell phone that is not listed in any public database. At this point, you have a few options. You can call the number back and ask who is calling, but only if you feel safe doing so. If the call seemed suspicious, it is safer to ignore it.
You can also block the number to prevent future calls. On iPhone, open the Phone app, find the number in Recents, swipe left, and tap Block. On Android, open the Phone app, find the number, press and hold it, then tap Block Number. Blocking does not tell you who called, but it stops them from reaching you again.
If you received a voicemail, listen to it carefully. Scammers often leave vague messages ("Call us back about your account"), while legitimate callers usually identify themselves and the reason for the call. If the message sounds suspicious, delete it and do not call back.
Frequently Asked Questions
Can I find out who called me if they blocked their number?
If a caller blocked their number, it will show as "Unknown," "Private," or "Blocked" in your call log. You cannot identify them through reverse lookup because no number is recorded. If they left a voicemail, listen to it for clues about who they are. Otherwise, there is no way to trace a blocked call.
Is it safe to call back a number I do not recognize?
It depends on what you know about the number. If you searched it and confirmed it belongs to a legitimate business or person you know, calling back is safe. If you have no information about it or found complaints that it is a scam, do not call back. Scammers use fake caller ID, so calling back may not reach the person who called you.
Why does my phone show a business name for some unknown callers?
Your phone uses caller ID databases to match incoming numbers to business names and locations. This works for most businesses because they register their phone numbers with carriers and directories. Personal cell phone numbers are usually not in these databases, so they show as "Unknown" or just a number.
What should I do if the same unknown number keeps calling me?
Repeated calls from the same number usually mean it is a scammer or robocaller. Search the number on complaint websites to confirm. Then block it in your phone's settings. If the calls continue from different numbers, contact your phone provider — they can help filter spam calls at the network level.
Can I report a number that keeps calling me?
Yes. You can report unwanted calls to the Federal Trade Commission at reportfraud.ftc.gov or by calling 1-877-438-4338. You can also report spam calls directly to your phone provider through their customer service line. Reporting helps authorities track patterns of scam calls, though it does not stop calls to your number immediately.