Sodium Phosphate
Base buffering salt – holds the formula's pH in range. Often works with citric acid or a citrate buffer. Without it, pH-sensitive actives (vit C, retinoids, acids) lose stability. Safe.
Supporting ingredient
It gives a product its texture, stability or shelf life. It has no claimed effect on the skin, so an efficacy tier does not apply. What is known about its safety is below
Tolerability and safety
- Irritation potential
- Low
- Allergen risk
- Low
- Pregnancy
- Safe
- Suitable for
- Normal, Dry, Combination, Oily, Sensitive
About this ingredient
Sodium Phosphate (Na3PO4) is an inorganic salt of phosphoric acid. In cosmetics it acts as a buffer: maintains the target formula pH together with citric acid or a citrate buffer. Mechanism. Paired with an acidic component it forms an equilibrium that holds pH in the desired range even when stray ions enter the formula. Without a buffer, pH-sensitive actives (vit C, retinoids, AHAs) lose stability quickly. Where applied. Vitamin C serums, acid toners, formulas with retinoids and AHAs. Final-product concentration is a fraction of a percent, near the bottom of the INCI list. Safety. CIR confirmed safety at cosmetic concentrations. Non-sensitizing, non-comedogenic. No systemic absorption. Pregnancy and lactation – safe.
Frequently asked questions
Is Sodium Phosphate safe during pregnancy?
Sodium Phosphate is considered safe during pregnancy at typical cosmetic concentrations. Systemic absorption through the skin is minimal.
What skin types is Sodium Phosphate for?
Sodium Phosphate suits: normal, dry, combination, oily, sensitive.
What is Sodium Phosphate and what does it do in cosmetics?
Base buffering salt – holds the formula's pH in range.
What's the INCI name for Sodium Phosphate?
The INCI name is Sodium Phosphate. It may also appear as: Na3PO4.
See Sodium Phosphate in a product composition right on the store page
The Evigrade extension adds an evidence panel to iHerb, Sephora, Druni and 12 more stores. This ingredient and every other one in the product show evidence-tier, allergen risk and pregnancy/lactation flags at a glance.
Similar role in the formula
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