Full disclosure: I am a massage therapist. I am self-employed and have never worked any other way, so take this advice with that in mind.
I do not expect tips or bonuses from my clients at Christmas. A few choose to do so anyway (very few – maybe half a dozen of my regulars, just to give you a benchmark), and it ranges anywhere from an extra $20 to a full session’s fee. I didn’t even know that people were “supposed to” include their massage therapists in the list of people to tip as Christmas until I read a few tipping guideline articles online. Really, if you tip your therapist all year long, there is no need. Even if you’re a non-tipper, we’re not expecting it — but we do know there are a few who’d prefer to hand over a chunk at once than do it in dribs and drabs throughout the year.
I believe if someone works in a spa or other massage establishment, Christmas bonuses come from their employer as they do in other industries. Certainly that has been the case for a few of my friends who have chosen to work in spas or gyms. So tipping in this situation makes even less sense than in mine.
My advice to anyone with a regular massage therapist: if you tip all year long, don’t bother. If you don’t, I suggest giving 1-2x the cost of your usual session depending on how often you see him/her. If you can’t bear the idea of ignoring your personal pain alleviator at Christmas, slip in a higher-than-usual tip and say something like, “there’s a little extra in there this time to get yourself a little something from me”. That way (a) we don’t start thinking you’ve decided to multiply your usual tip, and (b) we don’t come running after you to give it back, thinking you made a mistake…yup, I’ve done that. Sometimes my honesty borders on foolish.