A simplified passive extraction procedure for quantifying reduced inorganic sulfur compounds from sediments and water is presented. This method may also be used for the estimation of sulfate reduction rates. Efficient extraction of FeS, FeS2, and S2- was obtained with this procedure; however, the efficiency for S0 depended on the form that was tested. Passive extraction can be used with samples containing up to 20 mg of reduced sulfur. We demonstrated the utility of this technique in a determination of both sulfate reduction rates and reduced inorganic sulfur pools in marine and freshwater sediments. A side-by-side comparison of the passive extraction method with the established single-step distillation technique yielded comparable results with a fraction of the effort.