March 31, 2024, Bulgaria and Romania will be admitted to the Schengen area.
https://www.euronews.com/travel/2024/01/20/romania-and-bulgaria-will-enter-the-schengen-zone-in-2024-what-will-change-for-travellers
The article didn’t state if they were keeping their currencies. I understand that even if they move to the euro it will take awhile.
The Schengen treaty has nothing to do with currency.
The Schengen Zone has nothing to do with the Euro. The Schengen Zone is about the free movement of people across the borders.
The European Union is about the Euro (and other things). Bulgaria and Romania have been in the EU since 2007, but to this day they’re not allowed to implement the Euro because they still haven’t met the criteria set by the European Union.
Thank you Dutch traveler for the answer.
Land crossings will still have passport control, per the referenced article.