Although several novel approaches for hippocampal subregion delineation have been developed, they need to be applied prospectively and may be limited by long scan times, the use of high field (> 3T) imaging systems, and limited reliability metrics. Moreover, the majority of MR imaging data collected to date has employed a T1-weighted acquisition, creating a critical need for an approach that provides reliable hippocampal subregion segmentation using such a contrast. We present a highly reliable approach for the identification of 6 subregions comprising the hippocampal formation from MR images including the subiculum, dentate gyrus / cornu Ammonis 4 (DG/CA 4), entorhinal cortex, fimbria, and anterior and posterior segments of cornu Ammonis 1-3 (CA 1-3). MR images were obtained in the coronal plane using a standard 3D spoiled gradient sequence acquired on a GE 3T scanner through the whole head in approximately 10 minutes. The average ICC for inter-rater reliability across right and left volumetric regions-of-interest was .85 (range = .71 to .98; median = .86) and the average ICC for intra-rater reliability was .92 (range = .66 to .99; median = .97). The mean Dice index for inter-rater reliability across right and left hemisphere subregions was .75 (range = .70 to .81; median = .75) and the mean Dice index for intra-rater reliability was .85 (range = .82 to .90; median = .85). An investigation of hippocampal asymmetry revealed significantly greater right compared to left hemisphere volumes in the anterior segment of CA 1-3 and in the subiculum.