This is a frequently asked question. My answer is it depends on how well you care for your fresh new spray & how well you prepped your skin for it. 7-10 days is your usual time frame. It can go longer with proper care.
Lets go over a few tips on proper prep & maintenance for you skin to achieve the best & longest results possible.
Waxing or Shaving- If you wax you will want to do this at least 2 days prior to your spray tan treatment. The reason for this is that left over wax residue will block the absorption of the spray tanning solution. It's also important to note is that you will not want to wax after you tan because you will actually wax the spray tan off.
If you shave you will want to do this the night before the appointment, not the day of. This is because shave gels and lotions can leave residue on the skin which will prevent the airbrush tan from sticking and your pores may still be open and absorb too much solution in turn looking like dark dots all over.
Exfolitate- when you exfoliate your skin you are getting rid of the dead and dying skin that is ready to fall off, that way the tanning solution will adhere to your fresh, new skin. Some clients swear by using a dry brush or exfoliating mitt on dry skin. Be careful since most exfoliating products can leave a film on the skin's surface which could prevent the spray tanning solution from adhering, so I recommend using a glycerine soap. Never ever use oil based scrubs.
Moisturize- Lotion, lotion, lotion! The more hydrated your skin is, the longer your airbrush
tan will last. Apply a generous amount of lotion that is spray tan safe especially after your shower. Preferably twice a day. Remember pat yourself dry with a towel, do not rub.
Following these few simple tips will extend your airbrush tan to the fullest.