The SSA form (Static Single Assignment form) is used in compilers as an intermediate language as an alternative to traditional three-address code because code in SSA form is easier to analyse and optimize using data-flow analysis such as common-subexpression elimination, value numbering, register allocation and so on. We introduce RSSA, a reversible variant of the SSA form suitable as an intermediate language for reversible programming languages that are compiled to reversible machine language. The main issues in making SSA reversible are the unsuitability for SSA of the reversible updates and exchanges that are traditional in reversible languages and the need for ϕ-nodes on both joins and splits of control-flow. The first issue is handled by making selected uses of a variable destroy the variable and the latter by adding parameters to labels. We show how programs in the reversible intermediate language RIL can be translated into RSSA and discuss copy propagation, constant propagation and register allocation in the context of RSSA.