ESDU 81010 provides evaluated thermophysical properties data for ammonia on the saturation line. Equations, based on a critical evaluation of experimental data in the literature are given for the variation with temperature along the saturation line for the following liquid and vapour properties: density, specific enthalpy, specific heat capacity at constant pressure, dynamic viscosity and thermal conductivity. Also given are equations for the variation with temperature along the saturation line of the vapour pressure, latent heat of vaporisation, liquid specific heat capacity at saturation and surface tension. Saturation line properties in SI units, calculated from the equations are tabulated at 1 degree Celsius intervals from the melting temperature to 90 degrees Celsius. In the absence of experimental data, the tabulated data are extrapolated values and these are indicated in the tables. Conversion factors to facilitate use of the equations and tables in British units are included and graphs depicting the variation of the properties with temperature are presented. A full bibliography is given of the sources consulted.