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 Portugal 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 Euro (€)
Card usage
Card acceptance is widespread with chip & pin working flawlessly. Contactless also works fine and has been tested in stores such as Pingo Doce and Jumbo (supermarkets).
A small minority of terminals do not accept Mastercard.
A small number of stores claim to be ‘local card only’ and will tell you they don’t accept Visa or Mastercard but cannot justify it. Be aware of this and if you’re not looking for hassle, bringing a small amount of cash with you (making use of the free ATMs) is a good idea.
A few places are cash only.
ATMs
You should have no issues withdrawing cash from most ATMs with very few charging any fees at all. Please keep in mind this is at the major banks in Portugal and not the smaller ATMs available in malls and stores. Multibanco - a chain of ATMs similar to the likes of LINK have no fees across their network!
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
Public transport ticket machines require Magstripe withdrawals to be enabled.
The Lisboa Metro Network has 3G accessibility throughout and free wifi on platforms and stations so you should receive notifications instantly almost everywhere! 
Interesting fact courtesy of @anon44204028
Portugal has the highest proportion of cash machines in Western Europe with 1,516 machines per one million residents.
- Dec 2016
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