Not saying you’re wrong, but are you in the UK, by any chance? Seems rip-off international call pricing is especially rampant here (though oddly it only costs me 3p / minute to call the NL number above*).
*EDIT: Just for clarification, this is what my (mobile) provider is charging me. This is not a tariff that applies to all providers. Check with your provider for the tariffs they charge.