Sulfate-Free Aftercare: What Actually Helps After Colour or Keratin

What Sulfates Actually Do

Sulfates are what make regular shampoo foam up and feel like it's "really cleaning." They're effective at stripping oil and product build-up, which is exactly what you want most days — and exactly what you don't want right after colour or keratin, since the same stripping action also pulls colour molecules out of the hair shaft and breaks down the smoothing layer that keratin leaves behind.

What to Look For Instead

A sulfate-free shampoo cleans gently rather than aggressively, which is the whole point after a treatment. Check the ingredients list for sulfate-free labelling rather than relying on marketing language alone — "colour-safe" doesn't always mean sulfate-free, so it's worth actually checking.

How Long to Stick With Sulfate-Free Products

After colour, the general guidance is to stay sulfate-free indefinitely if you want the colour to hold its depth, though the first few weeks matter most. After keratin specifically, sulfate-free is even more important, since regular shampoo can noticeably shorten how long the smoothing effect lasts — using it from your very first wash after the treatment makes a real difference.

Other Aftercare Habits Worth Keeping

• Wait as long as recommended before the first wash after keratin, rather than rinsing early
• Use lukewarm rather than hot water, which also strips colour and smoothing treatments faster
• Add a leave-in or weekly mask if your hair feels dry, rather than washing more often
• Keep heat styling to a minimum in the first couple of weeks after either treatment