Ammonium bicarbonate

INS 503(ii)CAS 1066-33-7

Used as an acidity regulator — Codex also lists it as raising agent.

Ammonium bicarbonate, known to bakers as baker's ammonia, is a raising agent used in thin, dry biscuits and crackers. It decomposes completely to gases, leaving no residual salt taste.

Where it is and isn’t permitted

Status of Ammonium bicarbonate by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationPermitted21 CFR 184.1135retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

3 food categories

no numerical limit (good manufacturing practice)

Show every food category
  • 01.2.1.2 Fermented milks (plain), heat-treated after fermentation — GMP
  • 09.2.2 Frozen battered fish, fish fillets and fish products, including molluscs, crustaceans, and echinoderms — GMP
  • 13.2 Complementary foods for infants and young children — GMP
CXS 192-1995 Table Three, INS 503(ii)and 3 further provisionsretrieved 2026-09-07

What it is made from

Made by combining ammonia, carbon dioxide and water. It can only be used in low-moisture products, because in a moist food the ammonia would not fully escape.

  • Vegan
  • Vegetarian
CAS registry number
1066-33-7
InChIKey
ATRRKUHOCOJYRX-UHFFFAOYSA-N
PubChem
CID 14013

Every name it appears under

20 recorded names. A label may use any of them.

INS number

  • 503(ii)

CAS registry number

  • 1066-33-7

As it appears in regulation

  • Ammonium bicarbonate

Other names

  • Acid ammonium carbonate
  • Ammonium acid carbonate
  • AMMONIUM BICARBONATE
  • Ammonium bicarbonate (1:1)
  • Ammonium hydrogen carbonate
  • Ammonium hydrogencarbonat
  • Ammonium hydrogencarbonate
  • ammoniumbicarbonate
  • azanium;hydrogen carbonate
  • Carbonic acid, ammonium salt (1:1)
  • Carbonic acid, monoammonium salt
  • CCRIS 7327
  • HSDB 491
  • INS NO.503(II)
  • INS-503(II)
  • Monoammonium carbonate
  • NH4HCO3

Hazard reference values

No reference value for this substance in the sources we hold.

Evidence and how bodies read it

Studies, and the differing conclusions regulators drew from them, are curated by hand rather than machine-read, and none has been written for this substance yet.

Sources for this page

  • ecfr retrieved 2026-09-07
  • gsfa retrieved 2026-09-07

Full licence terms and publisher details on Sources. How this page is built and updated: Method.

Machine-readable:/api/v1/additives/ammonium-bicarbonate.json