It is The same as getting your hair cut, getting a pedicure, taking a taxi, etc. It is a service and a tip is appropriate. As always, about 15% is perfect, +/- depending on how satisfied you are.
Interesting. The reason why I initially asked this question is because I read an article about tip and it was saying that we put all type of service in the same mix pot. But in fact, from this article, we should care a bit more about which profession (type of service) we want to tip. For instance, it was said that a barman, who is paid (his base salary) in function of receiving a tip shoulda get tip from client if he provides a good service (amount 15% is generally the rule as you said). On the other hand, the amount should vary from 5% to 15% depending on which type of service you receive. As an example, for pizza delivery it should be 10% rather then 15%.
Then I started to think how much would it be for a massage. So I did a little research and I found (massage blog) that it should depends if you receive your service in a spa or from an independent. As an independent, the therapist can choose the rate of her service and should not expect a tip. Otherwise, in a spa, where therapist have lower salary it's encouraged to tips. For instance, in a spa, therapist have an hourly rate around 15$-25$ for a price (for client) around 70-100$ per hour compared to independent therapist who generally have a price in range of 60-80$.
So, from these points of view, the tip may vary in function of 2 criteria (are you satisfied of the service and what is the basic wage of the service provider (which type)).
Well I know it's only 5-10$ and some will say it's personal but I'm still curious what you guys think
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