What constitutes a “premium rated service”?

A premium-rated service is any service charged at a higher rate than the standard rate set by the mobile network for that particular service bearer on peer-to-peer (person-to-person) use. For example, peer-to-peer SMS costs N4 off-net. When a service is advertised, say on TV , asking that you text to a short code that charges N30, N50 etc, that is a “premium" rate.