A model and parameter extraction method for a substrate integrated waveguide (SIW) filter is presented. The proposed approach is derived from an analysis of full-wave simulations, allowing to obtain the equivalent circuit parameters for the iris. The accuracy of the method is demonstrated through a careful model–experiment correlation, allowing the correct representation of the SIW filter over the complete useful bandwidth. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2865–2868, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27183