You may need Google Translate, as this will be in Dutch:
http://nos.nl/artikel/2103141-ecb-s...-geldig.htmlIn summary: The ECB decided to stop the production of 500 Euro bank notes in 2018. The notes will hold their value from 2019 on, but will be taken out of circulation as soon as they're delivered at a bank.
The main reason for the European Central Bank to take this decision is that there's too much use among criminals. Right now there's still 300 billion Euro in 500 Euro notes circulating.
Apparently this decision isn't too popular for Germans, who apparently pay a lot more in cash than most other European do and apparently use these 500 Euro notes a bit more than most other Euro countries.