Most web browsers are able to detect your location, and will display local entries, along with telephone numbers first. Search online telephone directories specific to the United Kingdom to locate individuals and businesses. Typically, all that you need to search for an individual is their first and last name. Refer to a traditional phone book. Several companies deliver physical phone books directly to your doorstep.
The only way that you can legally trace a number is by matching it with public records. Beyond that, only the authorities can trace numbers. Report nuisance calls. If you are regularly receiving nuisance calls from the same number, you can report it to British Telecom. Oftentimes this will allow you to resolve the issue without getting the police involved. Call to report nuisance calls to BT. Contact a private investigator. You can hire a private investigator if you've hit a dead end.
Be aware that the investigator will only be able to search through public sources as well. These services aren't cheap, but can be much more thorough than a reverse phone lookup service. You may be able to find an investigator that will guarantee results or you get a refund.
Many require an upfront payment with no guarantee. Some private investigators will only take the case if the results are to be used in a legal case. Contact the authorities. If you are getting harassed by an unknown number, you can report it to the authorities.
Law enforcement personnel may be able to trace the phone number. Usually they will only do so if it is part of a larger case. You can find the contact information for your local police department at police. Contact your carrier. If you need to prevent a number from constantly harassing you, your carrier should be able to block it. This will prevent the number from being able to reach you.