These numbers generate an income for the company that uses them and the company that provides the number so call costs have to be paid.
As far as I can remember o2 have always charged for these and most 0800 numbers.
Ofcom has been working on the removal of these number types by introducing the 03 number range and most landline providers treat 03 numbers the same as a normal 01 02 number as do o2.
As said before use saynoto0870 to find a 01 02 number and then the call is included this also applies to landline calls as well as they also excluded those until recently on bt but other landline provioders may not follow bt's lead.
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My first mobile was in 1995 a CM-R111 from sony on Cellnet.
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