The present study explores the feasibility of the accumulation of polyhydroxyalkanoates (PHAs) under the presence of transient concentrations of added sodium chloride, by means of a mixed microbial culture (MMC). This culture was enriched on a mixture of volatile fatty acids (VFAs) containing 0.8 g Na+/L as NaOH. This MMC presented a maximum PHA accumulation capacity of 53 wt% with 27 Cmol% HV.