Rate My SPF

Disodium Phosphate

What Disodium Phosphate is & what it does

A buffering salt used alongside other phosphates to hold a formula at a stable, skin-friendly pH. It supports product consistency.

What is Disodium Phosphate and what does it do in sunscreen?

It is a pH adjuster, a buffering salt that helps hold a formula at a stable, skin-friendly acidity. A steady pH keeps the UV filters, preservatives, and texture behaving as intended over the life of the product. It is used in small amounts and has no effect you can feel on the skin.

Is Disodium Phosphate safe?

Yes. It is a simple, widely used buffering salt that is also a common food additive, and it is well tolerated on skin at the small levels used in cosmetics. It works on the chemistry of the formula rather than on the skin itself. It is not a common irritant.

Does Disodium Phosphate clog pores?

No. It is a water-soluble salt, not an oil or wax, so it has essentially no potential to block pores and is considered non-comedogenic. Its role is to balance pH, not to add richness. Any breakouts from a product are far more likely tied to its oils or emollients.

Is Disodium Phosphate a preservative?

No. It is a pH buffer, not a preservative, and it does nothing to stop microbes growing. It is sometimes confused with one because it helps keep the overall formula stable. The actual preserving is done by ingredients like phenoxyethanol or ethylhexylglycerin.

Why is Disodium Phosphate paired with other phosphates?

It is often used alongside a more acidic phosphate so the two together can hold a precise, stable pH, which is how a buffer system works. One leans basic and the other leans acidic, and the pair resists drifting in either direction. This keeps the sunscreen consistent from batch to batch and over time.

Sunscreens with Disodium Phosphate

We rate 214 sunscreens that contain it, showing the top 10 by overall score:

← All ingredients