It can be hard to tell sometimes when you are looking to book an appointment. You can usually get an idea by their pricing or even how they book appointments. If they are a bit lower in cost compared to others in the same area or if they seem to be booked on the hour every hour, then there is a good chance that you are paying for the time slot that you are booking for that appointment. Check to see if the website tells you. If you are still not sure, ask them, after all it is your time and money.
Personally, I believe that you get what you pay for, and set my appointments accordingly. If you book a 60, 90, or 120 minute massage, then you pay for a 60, 90, or 120 minutes of massage. I allow some extra time in between appointments to have time for clients to fill out any paperwork, discuss how they are feeling, what their goals are for the session, and to ask any questions before the session, as well as have time to talk after the session, pay, and schedule their next appointment. My regular clients have probably already realized this time concept. If a client arrives on time and we start the massage 10 minutes after the scheduled start time, I finish the massage 10 minutes past the end time. Your time is valuable and I believe that my services are of great value to you. Therefore you get what you pay for when you book an appointment with me.
When you are deciding to book your next appointment, make sure you know what you are paying for, as it is your time and money. You need to decide if saving some money to receive 10 minutes less of massage time is a good deal to you or not. Maybe the less time is better for your schedule and your budget. Maybe the extra time on the table is worth the extra cost. Regardless, knowing what you are paying for will help guide your expectations for your next appointment and allow you to get the most for your time and money.