People often post requests for the geographical alternative numbers for university phone systems.

Universities are defined as "public bodies" for the purposes of the FoI act, therefore we can request the geographical numbers under the act.

No doubt if the phones (in halls of residence in particular) are provided by a private company, the university might claim it doesn't know the number.

But I think it would be worth a try, for example for Oxford University, which has a single 0870 number for the whole university which is impossible to find by checking Ofcom's allocations.