The compound crystallizes in the aluminium trifluoride motif. Each fluoride is a doubly bridging ligand. The cobalt centers are octahedral.
CoF3 decomposes upon contact with water to give oxygen:
4 CoF3 + 2 H2O → 4 HF + 4 CoF2 + O2
It reacts with fluoride salts to give the anion [CoF6]3−, which is also features high-spin, octahedral cobalt(III) center.