The performance of anode-supported solid oxide fuel cells was investigated as the SDC buffer layer thickness was varied between similar to 0.4 mu m and similar to 2.3 mu m. The thickness of the buffer layer has a significant effect with the peak performance varying in magnitude by a factor of almost three. A peak power density of 1106 mW cm(-2) was achieved at 800 degrees C and an optimal SDC buffer layer thickness of similar to 1.5 mu m. The performance variation was complex due to a balance between ohmic and polarization losses, triple phase boundary area, pin holes and interfacial reactions between the BSCF + SDC cathode, SDC buffer layer, and YSZ electrolyte. Understanding this variation is essential in order to compare two fuel cells having a different porous buffer layer thickness. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.