The adipocyte-derived hormone leptin regulates appetite and energy homeostasis through activation of leptin receptors (ObR) on hypothalamic neurons, hence leptin must be transported through the blood-brain barrier (BBB) to reach its CNS target sites. During obesity however, leptin BBB transport is decreased, in part precluding leptin as a viable clinical therapy against obesity. Though the short isoform of the ObR (ObRa) has been implicated in the transport of leptin across the BBB due to its elevated expression in cerebral microvessels, accumulating evidence indicates leptin BBB transport is independent of ObRa. Here, we employed an ObR-neutralizing antibody (9F8) to directly examine the involvement of endothelial ObR in leptin transport across an in vitro human BBB model composed of the human endothelial cell line hCMEC/D3. Our results indicate that, while leptin transport across the endothelial monolayer was non-paracellular, and energy- and endocytosis-dependent, it was not inhibited by pre-treatment with 9F8, despite the latter’s ability to recognize hCMEC/D3-expressed ObR, prevent leptin-ObR binding and inhibit leptin-induced STAT-3 phosphorylation in hCMEC/D3 cells. Furthermore, hCMEC/D3 cells expressed the transporter protein LRP-2, capable of binding and endocytosing leptin. In conclusion, our results demonstrate leptin binding to and signalling through ObR is not required for efficient transport across human endothelial monolayers, indicating ObR is not the primary leptin transporter at the human BBB, a role which may fall upon LRP-2. A deeper understanding of leptin BBB transport will help elucidate the exact causes for leptin resistance seen in obesity and aid in the development of more efficient BBB-penetrating leptin analogues.