International mobile numbers

[Nocton]

I have an international call package with Plusnet which allows free international calls up to 30 minutes. At Christmas I usually call several overseas friends. Now I have received my December bill I noted that I had been charged about £10 for a 20-minute call to NZ. Having checked with Plusnet they say that it was a mobile no. and therefore not free. The number is not obviously different than others I rang in NZ and I was told that, unlike the UK, NZ does not clearly distinguish mobile nos. from others. So my question is how can I tell that it is a mobile no. before I call? Can someone recommend a good web site? I have done a web search and there seem to be lots of web sites, not all free and not all clearly 'safe'.

[Deev8]

... Plusnet they say that it was a mobile no. and therefore not free. The number is not obviously different than others I rang in NZ and I was told that, unlike the UK, NZ does not clearly distinguish mobile nos. from others.

All mobile phone numbers in NZ begin with 02 (so +64 2 when calling them from outside of NZ), no landline numbers begin with +64 2 (with one almost inconsequential exception - Scott Base in Antarctica is NZ territory and its phone numbers begin with +64 2409).

As far as a general resource for international telephone numbering schemes is concerned, I've always found Wikipedia to be quite useful, but you do have to wade through a lot of detail that you're probably not interested in - search for "Telephone numbers in [country name]".