The question we get most often isn't 'what should I use?' It's 'in what order?' Once you understand the underlying logic, product sequencing becomes intuitive rather than prescriptive.
The Core Rule: Thinnest to Thickest
Apply products from thinnest consistency to thickest: water-based toners and essences first, then serums, then moisturisers, then oils, then SPF (in the morning). Lighter, active-packed formulas need to reach the skin before denser, occlusive layers seal them out.
pH-Sensitive Actives
Some actives require a specific pH window to work. L-ascorbic acid and AHAs/BHAs work best at low pH (below 3.5). If you apply niacinamide directly after a low-pH acid, the acidic environment can temporarily affect niacinamide's efficacy. A 10-20 minute wait between actives resolves this, though the concern is often overstated in practice.
“Actives that conflict in theory often coexist perfectly well in practice, but when in doubt, separate them into morning and evening routines.”
