The problem of mass transfer at a microdisc electrodes placed in a parabolic steady channel flow is considered. Under suitable conditions, the transfer rate depends only on the Peclet number (a dimensionless measure of shear rate) and on the geometry of the electrode. We present a calculation of the mass transfer rate for a disc electrode for all Peclet number using two-point Pade approximations. The results are compared with existing analytical and experimental results. (c) 2006 Elsevier Ltd. All rights reserved.