Should I greet my customer at 6pm with "good evening" or "good afternoon"?

How should I greet my customer if I meet him/her at 6pm for a discussion? Should I say "good evening" or should I say "good afternoon"?

From my understanding, "good evening" is used at around 6pm, while "good afternoon" is used for from noon time until around 6pm.

Solution 1:

Both "Good afternoon" and "Good evening" are perfectly appropriate greetings at 6pm. Pick one, and don't overanalyze it. If you say "Good evening" at 4pm, or "Good afternoon" at 8pm, you might get funny looks, but near the boundary, either is fine.

Solution 2:

Good afternoon before sunset, Good evening after it?

Solution 3:

I think this is largely regional. In many places, "evening" starts at dusk, in others it starts at "dinner time" (6-7pm?) or "after business hours" (5pm).

My personal preference is usually to say "Good afternoon" until around 5pm, and then I switch to "Good evening." But you can always just avoid the situation and say "Hello!" instead. :)