The critical plane method has proven to be a popular analytical tool for estimating multiaxial fatigue. Based on the strain-life approach to fatigue, the method relies on a cycle counting routine to identify cycles and a damage model to assess damage for each cycle. Researchers have traditionally borrowed cycle counting methods from established uniaxial methods. This work will show how uniaxial rainflow methods are inappropriate for cycle counting on the critical plane. A multiaxial cycle counting method, based on a simple uniaxial rainflow algorithm, is then presented.