Tungsten hexachloride is the chemical compound of tungsten and chlorine with the formula WCl₆. This dark violet blue species exists as a volatile solid under standard conditions. It is an important starting reagent in the preparation of tungsten compounds. WCl₆ is a rare example of a charge-neutral hexachloride, another example being ReCl₆. Better known than WCl₆ is the still more volatile WF₆.

As a d⁰ ion, W(VI) forms diamagnetic derivatives. The hexachloride is octahedral with equivalent W–Cl distances of 2.24–2.26 Å.

Tungsten hexachloride can be prepared by chlorinating tungsten metal in a sealed tube at 600 °C:

Tungsten (VI) chloride is a blue-black crystalline solid at room temperature. At lower temperatures, it becomes wine-red in color. A red form of the compound can be made by rapidly condensing its vapor, which reverts to the blue-black form on gentle heating. It is readily hydrolyzed, even by moist air, giving the orange oxychlorides WOCl₄ and WO₂Cl₂, and subsequently, tungsten trioxide. WCl₆ is soluble in carbon disulfide, carbon tetrachloride and phosphorus oxychloride.

Methylation with trimethylaluminium affords hexamethyl tungsten:

Treatment with butyl lithium affords a reagent that is useful for deoxygenation of epoxides.

The chloride ligands in WCl₆ can be replaced by many anionic ligands including: Br⁻, NCS⁻, and RO⁻ (R = alkyl, aryl).

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