The new number is 03303 211707

The old 07010 707237 is being phased out.

For the time being the 08707 650551 is still operable.

To understand the costs involved below is information taken from http://consumers.ofcom.org.uk

03 numbers
How much do calls cost? Calls cost no more than calls to geographic numbers (01 or 02) and must be included in inclusive minutes and discount schemes in the same way. Calls from landlines are typically charged up to 10p per minute; calls from mobiles typically cost between 10p and 40p per minute. Calls from landlines and mobiles are included in free call packages.

0870 numbers
How much do calls cost? Calls from some landline providers cost no more than a geographic rate call (01 or 02, up to 10p plus a call set-up fee in some cases) and may count towards any inclusive minutes in the same way. Calls from other landline providers typically cost up to 11p per minute. From some mobile networks calls typically cost between 14p and 41p per minute. Recently some other providers have also included calls to 0845 and 0870 numbers in call packages, making them free at certain times of the day.

0871 numbers
How much do calls cost? Calls typically cost between 11p and 15p per minute for landline customers, plus a call set-up fee. From a mobile phone, calls may cost between 20p and 41p per minute.

070 numbers
How much do calls cost? 070 numbers can cost between 4p and 52p per minute if calling from a landline (and often include a call set-up fee, sometimes of up to 51p). From a mobile phone these numbers can cost between 30p and £1.50 per minute.