This is a wiki crowdsourced by the Monzo Community to help you travel with Monzo.
Just like Wikipedia, anyone can edit it to help out others. If you have any tips or feedback for visiting Hong Kong with Monzo, please feel free to edit this guide. You can also add a comment or question below — someone will then incorporate your comment into the main text below and then delete your comment. To create your own “Monzo in …” guide if one doesn’t already exist, just copy this template into a new post and write away!
Safe travels! 
Currency
The official currency is the Hong Kong dollar (HK$)
Card usage
Card acceptance is widespread with chip & pin and contactless however a number of shops will not accept Mastercard so be aware and bring cash or an alternative means of payment for the time being. Your payments may need to be put through as either credit or debit depending on the terminal. You may be asked to sign your name after the transaction is processed.
Make sure that you ask to be charged in HKD rather than them converting and performing the transaction using GBP.
ATMs
ATMs are generally plentiful and fee-free from Citibank, Hang Seng Bank, BEA, BOCHK or the more wide-spread HSBC. There have been reports of cards being declined however enabling the magstripe from the app every 24 hours should solve the problem.
Payment and withdrawal limits
All Monzo cards have some payment and withdrawal limits. To check yours before you leave, go to your Profile section of the app and tap on Limits.
Crowdsourced merchant data
Data will most likely be scant so please try and contribute relevant feedback about transactions 
Miscellaneous
The Octopus Card may be handy within the city for public transportation as credit/debit cards are not accepted. The card also works at a variety of shops so could be a handy back-up just in case Monzo isn’t being accepted! You can pick up an Octopus card from the airport using your Monzo card at the Octopus Vending Machines. They’re located just by the HK Airport Express entrance.
To edit this guide, just tap the pencil icon below. Alternatively, add a reply with your comments and someone from the community will incorporate your suggestions into the guide and then delete your comment.