Ingredient dictionary

Disodium Phosphate

Also listed as: Disodium hydrogen phosphate, Sodium phosphate dibasic

Disodium Phosphate is a salt of phosphoric acid and sodium. In skincare and haircare it mainly works as a buffer, helping keep a product's pH steady. It is on the label of 33 products in our library. Checked against our library November 6, 2026.

The catch: none for most people; check the full product list if your skin reacts easily.

What Disodium Phosphate does

Adjusts the pH of a formula
Buffers pH against small shifts
Helps keep the formula stable

Disodium Phosphate is a salt. It is made by neutralizing phosphoric acid with a sodium base, such as sodium carbonate or sodium hydroxide. The result is a white powder that dissolves easily in water. It is also used outside beauty, including in foods and cleaning products.

Formulators use it mainly as a buffer. A buffer is a mix that resists sudden changes in pH, the measure of how acidic or basic a product is. Keeping pH steady helps a formula stay stable over time and feel comfortable on skin. It blends easily into the water phase of creams and lotions.

Good for

Suits hand creams, foot care and leave-in products, where a steady pH helps keep the formula stable.

Be careful if

Nothing in particular for most skin types.

Frequently asked questions

Is Disodium Phosphate safe for skin?

It is generally well tolerated at the levels used in cosmetics, and it is not flagged in any of our ingredient families. If your skin is sensitive, patch test a small area first.

Why is Disodium Phosphate in hand cream?

Many hand creams are water-based, and pH can shift as a product ages. Disodium Phosphate acts as a buffer to hold it steady. It works quietly in the background, so you rarely notice it.