The author studies elliptic hypergeometric series on root systems. He obtains elliptic analogues for the Gustafson–Milne type series on the root systems

${A}_{n}$,

${C}_{n}$ and

${D}_{n}$. In the case of root systems

${A}_{n}$ and

${D}_{n}$ the proof is based on an elliptic partial fraction expansion and an induction. For this root system

${C}_{n}$ the multivariable hypergeometric summations are obtained through convenient determinant evaluations. The main formula is deduced as a special case of a multivariable Jackson sum of

*S. O. Warnaar* [Constructive Approximation, 18, 479-502 (2002;

Zbl 1040.33013)]. From these summation and transformation formulas there are deduced corresponding elliptic Bailey transformations.