If you have short hair or are just looking to top up your colour, 1 bottle will do the job. We would recommend 2 bottles for lighter colours on short hair just so you can fully saturate each strand. 2 bottles for mid length hair - you need that full saturation and all important smooshing of the colour on your hair! Longer hair will need around 3-4 bottles to make sure every strand gets an even dose of colour.
