Calls to 0203 numbers are normally charged the basic or local rate.
Calls from landlines are typically charged up to 16p per minute. Many providers charge a 23p call set-up fee (or 'connection charge'), but this can vary. Call charges are dependent on the time of day, and most providers offer call packages that allow calls free of charge at certain times of the day.
Call costs from mobiles vary according to the calling plan chosen. Typically, they are included in free call packages. However, if you call an 01/02 number outside of any inclusive minutes, they can cost between 3p and 65p per minute.