Rhenium trioxide chloride is an inorganic compound with the formula ReO3Cl.

[1] The material is used as a reagent in the preparation of rhenium compounds.

[3][4] The compound hydrolyzes readily to give perrhenic acid.

The compound adopts a tetrahedral structure with Re-O and Re-Cl bond distances of 1.71 and 2.22 Å.

[5] In contrast rhenium trioxide fluoride (ReO3F) is polymeric with octahedral Re centers.