I have some older version of Euros from past trips. When I purchased some Euros recently they look different. When I did research on line, it appears the older version Euros were issued around 2002 and since then they issued from 2013 to 2019 newer version. Can I still pay with the older version of Euros?
Yes, a new series of bills has been issued, and older bills are being replaced by the banking system, but all Euros are still legal tender.
Another yes. At the end of our trips, I ensure I only bring home the newest notes just to play it safe.
Even if the old version of bills are considered obsolete, has not yet been declared when will be not accepted. So at the moment everybody still accept that bills without problems: shops, restaurants, ATM...