A rapid, selective and sensitive high performance liquid chromatographic method for the estimation of efavirenz in human plasma has been developed. Chromatography was carried out on a Denali C18 column using a mixture of phosphate buffer (pH 3.5 ± 0.05) and acetonitrile in a ratio of 60 : 40 v/v as the mobile phase. The eluates were monitored at 247 nm. Carbamazepine was used as an internal standard. The retention times for efavirenz and carbamazepine were found to be 15.4 and 2.3 min, respectively. The method was found to be linear in the concentration range of 40.0 ng/mL to 4003.9 ng/mL. The method validated as per FDA guidelines and was found to be suitable for bioequivalence and pharmacokinetic studies.