The propanoate or propionate ion is C2H5COO (propanoic acid minus one hydrogen ion).

A propanoic or propionic compound is a small salt or ester of propanoic acid. In these compounds, propanoate is often written in shorthand, as CH3CH2CO2 or simply EtCO2.

Propanoates should not be confused with propenoates (commonly known as acrylates), the ions/salts/esters of propenoic acid (also known as 2-propenoic acid or acrylic acid).

The misspelling "proprionate" is often encountered.