Sodium nitrate

E number E251INS 251CAS 7631-99-4

Used as a preservative — Codex also lists it as colour retention agent.

Sodium nitrate is used in slow-cured meats such as dry-cured hams, where bacteria convert it gradually to nitrite over months. It is a reservoir rather than an active curing agent.

Where it is and isn’t permitted

Status of Sodium nitrate by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationPermitted, with conditions21 CFR 172.170retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

1 food category

highest permitted level 35 mg/kg

CXS 192-1995 Table One, INS 251, food category 01.6.2retrieved 2026-09-07

What it is made from

Mined as Chile saltpetre or manufactured by neutralising nitric acid with sodium. Nitrate also occurs at high levels in leafy vegetables, which are a larger dietary source than cured meat for most people.

  • Vegan
  • Vegetarian
CAS registry number
7631-99-4
InChIKey
VWDWKYIASSYTQR-UHFFFAOYSA-N
PubChem
CID 24268

Every name it appears under

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

E number

  • E251

INS number

  • 251

CAS registry number

  • 14797-55-8
  • 15621-57-5
  • 7631-99-4

As it appears in regulation

  • Sodium nitrate

Other names

  • 0.001M Sodium nitrate
  • 8M4L3H2ZVZ
  • Caswell No. 781
  • CCRIS 558
  • Chile salpeter
  • Chile saltpeter
  • Cubic niter
  • E 251
  • E 251-252
  • EPA Pesticide Chemical Code 076104
  • etabisulfite
  • HSDB 726
  • INFLAMMATIONS
  • INS NO.251
  • INS-251
  • NaNO3
  • Natrum nitricum
  • Nitrate
  • Nitrate de sodium
  • Nitrate of soda
  • Nitrate, sodium
  • NITRATES
  • Nitratine
  • Nitratite (Na(NO3))
  • Nitric acid monosodium salt
  • Nitric acid sodium salt (1:1)
  • Nitric acid, sodium salt
  • Nitrogen and oxygen isotopes in nitrate, NIST(R) RM 8569
  • Saltpeter (Chile)
  • Saltpeter (Chile) (VAN)
  • Soda niter
  • Sodium nitrate
  • Sodium nitrate (NaNO3)
  • Sodium nitrate(DOT)
  • Sodium nitrate, 99.995% trace metals basis
  • Sodium nitrate, 99.999% (metals basis)
  • Sodium nitrate, >=99.0%, plant cell culture tested
  • Sodium nitrate, ACS reagent
  • Sodium nitrate, ACS reagent grade
  • Sodium nitrate, ACS reagent, >=99.0%
  • Sodium nitrate, analytical standard
  • Sodium nitrate, anhydrous, 99.995% trace metals basis
  • Sodium nitrate, anhydrous, free-flowing, Redi-Dri(TM), ReagentPlus(R), >=99%
  • Sodium nitrate, AR, >=99.5%
  • Sodium nitrate, beads, 1-2 mm, 98%
  • Sodium nitrate, BioUltra, >=99.0% (T)
  • Sodium nitrate, BioXtra, >=99.0%
  • Sodium nitrate, JIS special grade, >=99.0%
  • Sodium nitrate, LR, >=98%
  • Sodium nitrate, meets analytical specification of FCC, E251, 99.0-100.5%
  • Sodium nitrate, p.a., ACS reagent, reag. ISO, reag. Ph. Eur., 99%
  • Sodium nitrate, puriss. p.a., ACS reagent, reag. ISO, >=99.5%
  • Sodium nitrate, ReagentPlus(R), >=99.0%
  • Sodium nitrate, SAJ first grade, >=99.0%
  • Sodium saltpeter
  • sodium trioxidonitrate(1-)
  • Sodium(I) nitrate (1:1)
  • sodiumnitrate

Systematic names

  • Nitrate
  • sodium nitrate
  • Sodium nitrate, containing in the dry state more than 16,3 per cent by weight of nitrogen

Hazard reference values

Values set by assessing bodies. A body that has not set a value is not listed here.
TypeValuePopulationAssessed byOpinion
ADI3.7 mg/kg bw/dayconsumersEFSA ANS2017
ADI3.7 mg/kg bw/dayadultsEFSAnot identified in the dataset
ADI3.7 mg/kg bw/dayconsumersEFSAnot identified in the dataset

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/sodium-nitrate.json