Not in costume. We sometimes go out to greet patrons, friends, family, etc. after the show, but not in costume OR character. The only exception is our Gala Night, an additional fundraiser for our group. The actors are required to mingle in costume with the patrons after that show. That's only once a year however.

 

I feel like the receiving line sort of thing feels like the cast is going out simply to get accolades for their performances.  It's really awkward if the show was a bomb...

 

I also don't like that as cast tends to go out in costume.  Whether you tell them to or not - some of them end up out in the lobby with costume, eating, drinking, smoking, etc.  I won't tell you how many times I've had costumes ruined or had to be run for an emergency cleaning due to actors getting excited meeting their "public".  If they have friends in the audience, the friends will wait for a little bit while they change their clothes and can come out to personally meet them.  If that expectation is set early on - there are no surprises!