There are numerous reasons for tracing the origin of an international call. Fortunately, due to an international system that determines how telephone numbers are created, uncovering the origin of an international call is relatively easy. Each country has a one-, two-, or three-digit "country code" and most countries will also have regional codes, equivalent to the American "area code." With free Internet-based search tools and the prevalence of caller ID technology today, tracing the origin of an international call is quite easy.
Obtain the phone number you wish to trace. If the number appeared on your caller ID, simply write down the number. If the number did not appear on caller ID, call your phone carrier to obtain the international number from which you were called.
Navigate to a website that can trace international calls, such as TP2, listed in the Resources section of this article. Enter the entire phone number into the search box with no other symbols or spaces.
Solve the CAPCHA form, which is a pop-up box with letters and numbers that need to be copied to continue using the service. An online reverse phone search will usually will give the country and region from where the phone call originated.
Consult a chart of country codes if an online service is unable to locate the origin of the call (see Resources). Search the list for the country code at the beginning of the phone number. If searching manually, it helps to have some idea of the possible origin of the call, as country codes may be one, two or three numbers long.