As part of its national telephone numbering plan, Ofcom will be introducing 03 numbers later this year as an alternative to chargeable 08 numbers such as 0870. These numbers will cost exactly the same as geographic 01 and 02 numbers, and therefore be allowed as part of any inclusive minute allowances or call discount schemes in exactly the same way as their geographic cousins.
Initially, some of the 03 number range will be reserved for holders of certain 08 numbers. This will allow businesses to change their 08 number to its 03 equivalent if they deem it necessary.
0845 -> 0345
0844 -> 0344
0870 -> 0370
0871 -> 0371