As long as the country you are visiting supports the issuing organization of the credit card held by the cardholder when the merchant's POS machine swipes the card.

For example, if the POS machines in the hands of merchants in the UK support UnionPay lines, cardholders can pay with their UnionPay credit cards.

For example, if the POS machines in the hands of merchants in the UK support card issuing organizations such as VISA, MasterCard, AE, JCB, or Diners Club, then the cardholder’s credit card from the corresponding card issuing organization can be used.

Of course, in developed countries such as Europe and the United States, VISA and MasterCard are the most mainstream POS lines, so UnionPay, VISA or MasterCard dual-label cards or card sets are the best choices.