A fixative slows down how quickly the more volatile top and heart notes evaporate, which is what gives a perfume staying power instead of vanishing within the first half hour.

How it actually works

Lighter molecules, citrus oils especially, evaporate fast because they’re small and volatile by nature. Heavier base materials like musk, amber, oud and certain woods evaporate far more slowly, and when they’re blended alongside lighter notes they physically slow the whole mixture’s evaporation rate, a bit like adding weight to something that would otherwise blow away. This is why a citrus-heavy perfume with no real base fades so much faster than a woody or amber one built the same way in every other respect.

Common fixatives you’ll actually see listed

  • Musk, natural or synthetic
  • Ambergris substitutes like ambroxan
  • Resins such as labdanum and benzoin
  • Heavy woods like sandalwood and oud

It’s exactly why oud and amber-heavy Arabian perfumery tends to have such famously long wear compared with lighter Western colognes. Our guide to how perfume is made and the complete guide to perfume both explain this in more depth.