How do you say good evening in flemish?

The most common way to say "good evening" in Flemish is "goeie avond".

It's important to note that Flemish is a dialect of Dutch, so you can also use the standard Dutch phrase "goedemiddag" (which is technically "good afternoon," but it's often used in the evening as well).

However, "goeie avond" is more common in everyday speech in Flanders.