It is obtained by heating white phosphorus at 540 - 570K out of contact with air in an inert atmosphere ( CO₂ or coal gas) for several hours.

Red phosphorus exists as chains of P₄ tetrahedra linked together through covalent bonds to give a polymeric structure as shown.

Due to its polymeric structure, red phosphorus is much less reactive and has m.p. much higher than that of white phosphorus.

Red phosphorus is a hard, odorless, non poisonous solid, insoluble in organic solvents such as CS₂ , alcohol and ether. Its ignition temperature is much higher than that of white phosphorus and thus does not catch fire easily. It does not show phosphorescence.

It sublimes on heating giving vapors which condense to give white phosphorus. It is denser than white phosphorus and is a bad conductor of electricity.

t burns in oxygen at 565K to give phosphorus pentoxide, reacts with halogens, sulfur and alkali metals only when heated forming their corresponding salts.

It does not react with caustic alkalies and this property is made use in separating red phosphorus from white phosphorus.