I would never accept a free session (highly doubt that any therapist would offer one anyway). Not because of guilt (why feel guilty?) but because the money is there to compensate for the fact that this is a one-sided relationship. Well on paper at least. If a therapist offers free sessions, the worry is that they'll start feeling resentful if/when the client is upset/angry/critical at some point or another. I know people here say that: well therapists are grown-*** adults and nobody is forcing them to offer free sessions. The fact is a lot of therapists have no self-awareness and don't seem to think much about things at all. We see this enough on this forum. My ex therapist started resenting me at some point because she felt I was asking for too much even though she had previously said it was ok and that she was fine with me emailing/texting. And I always paid her handsomely and on time.