The main feedstock for the value-added phosphorus chemicals used in industry and research is white phosphorus (P ₄), from which the key intermediate for forming P(III) compounds is PCl ₃. Owing to its high reactivity, syntheses based on PCl ₃ are often accompanied by product mixtures and laborious work-up procedures, so an alternative process to form a viable P(III) transfer reagent is desirable. Our concept of oxidative onioation, where white phosphorus is selectively converted into triflate salts of versatile P ₁ transfer reagents such as [P(L _N) ₃][OTf] ₃ (L _N is a cationic, N-based substituent; that is, 4-dimethylaminopyridinio), provides a convenient alternative for the implementation of P–O, P–N and P–C bonds while circumventing the use of PCl ₃. We use p-block element compounds of type R _nE (for example, Ph ₃As or PhI) to access weak adducts between nitrogen Lewis bases L _N and the corresponding dications [R _nEL _N] ²⁺. The proposed equilibrium between [R _nEL _N] ²⁺ + L _N and [R _nE(L _N) ₂] ²⁺ allows for the complete oxidative onioation of all six P–P bonds in P ₄ to yield highly reactive and versatile trications [P(L _N) ₃] ³⁺. [Figure not available: see fulltext.]