Phone numbers to landlines have area codes by regions and cities. If you are calling to landlines in the UK, it is either a local or long distance calls.
For long distance, calls are often paid higher rates. The following list of city area codes in the UK is used to determine where the phone number is located and it allows you to limit the outgoing long distance calls. Every landline phone number in the UK starts with this area code, which can be easily found in the following summary list.