The capacitated warehouse location problem consists of the well known transportation problem with the additional feature of a fixed charge associated with each warehouse which is put to use. The problem is usually solved as a special type of mixed integer programme, so that relaxation and lower bounding are a vital part of any algorithm. A deeper insight into the relaxation process may eventually lead to more efficient algorithms for the problem. It is shown here that the LP relaxation of the capacitated warehouse location problem can incorporate constraints of a much more general nature than those previously described.