The thermoelectric power of Bi2Sr2CaCu2Ox and iodine-intercalated Bi2Sr2CaCu2Ox crystals has been measured between the transition temperature and 290 K. Both the magnitude and the temperature dependence are in substantial agreement with data on polycrystalline material in which the doping level, and Tc, were altered by Pb substitution and oxygen loading. The results support the view that the suppression of Tc upon intercalation arises predominantly from an increase in the hole concentration on the superconducting CuO2 planes, with at most a small change due to the expansion along the c-axis. © 1995.