How to identify a phone operator by number
The first digits of a phone number aren't just a city code. Here's how to read them to find out which carrier and region are behind an unfamiliar call.
What a number is made of
A Russian mobile number starts with +7 (or 8) and a three-digit code — say, 903 or 926. That's called the DEF code, and it used to be tightly bound to a specific carrier. Since 2013, mobile number portability (MNP) lets subscribers keep their number when switching carriers, so the code shows who the range was originally issued to, not necessarily the current owner.
Looking up the carrier by code
The easiest way is to check an operator code directory: for a given three-digit code it lists the carrier the range was issued to and the region. Keep in mind that because of number portability, the actual current carrier for a specific subscriber can differ from the one tied to the range.
What a number lookup adds
Besides the technical carrier and region, KtoTam.to shows a number's reputation — reviews from other users, spam signals, and whether it's confirmed by the owning organization. That's a fuller picture than the carrier code alone.
How to check a number quickly
- Open the operator code directory and enter the first three digits after +7
- Compare the listed region with where you expect the call to be from
- Enter the full number into KtoTam.to to see its reputation and reviews
- Remember: because of number portability, the code doesn't guarantee the current carrier