Tried using my new current account card to top up my metro card. Initially selected debit card but was rejected saying it was a credit card. Tried pressing credit card next and got as far as entering the zip code (00000 works on my normal credit card). My account was charged but the transaction was rejected.
I had the same experience a few months ago with the prepay card and the money was returned in about a week.
Anyone had any better success?
I used the machines fine earlier in the year. Think I entered 10001 which is a valid zip code for NYC. They are getting contactless soon so wonât be an issue for much longer
Itâs worth noting that 99999 is the correct zip code to be using when at MTA machines. If your transaction failed out at this stage using any other zip code, you can either wait for the automatic reversal in 7â8 days or get in touch with the current account support team in the app. 
When a credit card is used at an MVM, the MVM will ask you to enter your zip code for verification. However, if your credit card account has a billing address outside of the United States, you are not subject to the zip code verification requirement. Instead, type in â99999â when prompted for a zip code. This will indicate to the MVM that an international credit card is being used, and the regular transaction authorization process will still take place.
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Thanks for the replies. Iâll try five nines next time I top up. I did ask one of the staff there but they suggest five zeros or four nines.
After three incorrect attempts I didnât want to keep on racking up charges, albeit temporary, on my card.
On the subject of contactless I tried to use it in the best buy but it was also rejected. Had to use chip and pin. Donât know if thatâs because they havenât fully rolled out the system.
Alas, another attempt, another charge, another declined transaction. This time I tried five 9s.
I forgot about the 10001 suggestion so maybe Iâll give it one more shotâŚ
Sorry didnât see this thread earlier! We added a fix for New York MTA ticket machines on the current account just before Christmas: if the ticket machine requests you to enter a zip code for your Monzo current account debit card, you can input any number to proceed. 
Weâll use this workaround for any US self-service terminals that request a zip code (e.g. ticket machines and automated fuel dispensers). Weâre fixing these on a case-by-case basis so if you find a terminal or merchant where this doesnât work, please let us know via in-app chat! 
Thatâs good to hear, I tried about two weeks before Christmas and couldnât get any to work
If Monzo is the one declining transactions because of wrong ZIP code, would it be possible to say so in the decline notification, and provide the official workaround from a MasterCard which is (if I remember right) to zero-pad the digits of your postcode up to 5 digits?
This will all be moot, soon. I believe that the same company which provides Tfl with contactless will be providing the New York metro system, and that the Metro card will become obsolete.
Yes. About time!