The solution of large and complex electromagnetic (EM) problems often leads to a substantial demand for high-performance computing resources and strategies. This is true for a wide variety of numerical methods and applications, ranging from EM compatibility to radio-coverage, circuit modeling, and optimization of components. In the last decades, graphics processing units (GPUs) have gained popularity in scientific computing as a low-cost and powerful parallel architecture. This paper gives an overview of the main efforts of researchers to port computational electromagnetics (CEM) codes to GPU. Moreover, GPU implementation aspects of two well-known techniques, namely the finite-difference time domain (FDTD) and the method of moments (MoM), are investigated. The impressive speed-ups achieved (up to 60× and 25× for FDTD and MoM, respectively) demonstrate the effectiveness of GPUs in accelerating CEM codes. Copyright © 2012 John Wiley & Sons, Ltd.