The amount of time your hair colour will last varies depending on the hair colour type chosen. As the name suggests permanent hair colour, including Préferénce & Excellence, will provide long lasting colour with a retouch required once the hair has new growth. Hair coloured with long-lasting semi-permanent dye, or ‘demi colour’, will gradually fade with each shampoo, but generally last around 28 washes. This includes Casting Crème Gloss. Semi-permanent colour, including Age Perfect and Colorista Semi-Permanent will last around 10-20 shampoos. For instant root coverage that will wash out with one shampoo use Magic Retouch.