Sodium Ascorbyl Phosphate
A stable, water-soluble derivative of Vitamin C that converts to L-Ascorbic Acid once absorbed into skin. Formulated at a near-neutral pH, making it far gentler than pure L-Ascorbic Acid — a common pick for sensitive and acne-prone skin.
Typical concentration
5–15%
Formulation pH
6–7 (near neutral)
What SAP is used for
- Gentle brightening with lower irritation risk
- Has mild anti-bacterial properties, useful for acne-prone skin
- More stable and longer shelf life than L-Ascorbic Acid
Stability
Stable at neutral pH; tolerates normal room-temperature storage far better than L-Ascorbic Acid.
Advantages
- Gentle on sensitive/acne-prone skin
- Good shelf stability
- Works at skin-friendly neutral pH
Limitations
- Weaker, slower-acting than L-Ascorbic Acid
- Less clinical data on collagen-boosting effect
Commonly paired with
Use with care alongside
How SAP compares with other vitamin C forms
| Form | Typical concentration | pH |
|---|---|---|
| L-Ascorbic Acid | 8–20% (10–15% is the effective, well-tolerated sweet spot for most skin types) | Below 3.5 for optimal skin penetration |
| Sodium Ascorbyl Phosphate | 5–15% | 6–7 (near neutral) |
| Magnesium Ascorbyl Phosphate | 3–10% | 6–7 |
| Tetrahexyldecyl Ascorbate | 5–20% | Flexible, works across a wide pH range |
| Ascorbyl Glucoside | 10–25% | 5–7 |
| 3-O-Ethyl Ascorbic Acid | Retail serums commonly list 10–15%. There is no well-established optimum from independent clinical studies, and percentages are not directly comparable with L-ascorbic acid. | Does not need the very low pH that L-ascorbic acid does; formulas are usually mildly acidic |
Serums using Sodium Ascorbyl Phosphate
No published serum in our database currently lists Sodium Ascorbyl Phosphate as its vitamin C form. Browse all serums.
Sodium Ascorbyl Phosphate: quick answers
+What is Sodium Ascorbyl Phosphate?
A stable, water-soluble derivative of Vitamin C that converts to L-Ascorbic Acid once absorbed into skin. Formulated at a near-neutral pH, making it far gentler than pure L-Ascorbic Acid — a common pick for sensitive and acne-prone skin.
+What concentration of Sodium Ascorbyl Phosphate is typical?
5–15%
+What pH does Sodium Ascorbyl Phosphate need?
6–7 (near neutral)
+How stable is Sodium Ascorbyl Phosphate?
Stable at neutral pH; tolerates normal room-temperature storage far better than L-Ascorbic Acid.
Who it may suit
Related guides
Sources
- Al-Niaimi F, Chiang NYZ. Topical Vitamin C and the Skin: Mechanisms of Action and Clinical Applications. J Clin Aesthet Dermatol, 2017.
- Telang PS. Vitamin C in dermatology. Indian Dermatology Online Journal, 2013.
- Pinnell SR et al. Topical L-ascorbic acid: percutaneous absorption studies. Dermatologic Surgery, 2001.
We are not dermatologists and this page has not been medically reviewed. It is for information only — consult a qualified professional before making decisions about your skin.