From today's NZ Herald, can't seem to find it on the website yet
The overseas cash advance/withdrawal fee for all ASB Credit cards, Debit cards and Fastcash cards has been removed. Was previously $7.50.
The ATM/FastPhone/Fastnet Classic cash advance fee for all ASB Credit cards has been removed. Was previously $2.00.
The teller assisted cash advance fee for all ASB Credit cards has decreased from $5.00 to $3.00.
The offshore service margin for refunded purchases on ASB Visa Credit cards and ASB Visa Debit cards has been removed.
These changes are effective from 14 February 2019.
Based on the above info, it appears that using an ASB Fastcash card in an overseas ATM only charges you 1.1%. This is by far the cheapest way to use overseas ATMs with cards issued by any NZ bank.
** The Offshore Service Margin is 1.10% for a FastCash overseas withdrawal and 2.10% for a Visa overseas transaction.