PCl₃ is important indirectly as a precursor to PCl₅, POCl₃ and PSCl₃. which in turn enjoy many applications in herbicides, insecticides, plasticisers, oil additives, and flame retardants.

For example oxidation of PCl₃ gives POCl₃, which is used for the manufacture of triphenyl phosphate and tricresyl phosphate, which find application as flame retardants and plasticisers for PVC. They are also used to make insecticides such as diazinon.