Merchants in Hong Kong basically support UnionPay cards, which are free and automatically settled in RMB without purchasing foreign exchange.

Those with the UnionPay logo on the ATM can withdraw money from the ATM, but according to the international withdrawal, a handling fee will be charged (different banks vary from 4 yuan to 20 yuan every time).

However, your debit card is better to be a UnionPay standard card, which is the card starting with 622. UnionPay standard cards go through the UnionPay network smoothly, and cards beginning with 955 sometimes get stuck in the network.