In general, one filter paper is sandwiched between two sacrificial papers to prevent fouling or contamination of the paper used for the measurement. After attaining the equilibrium between the filter paper and the unsaturated soil sample, the moisture content of the filter paper is measured gravimetrically. The measured gravimetric moisture content is related to matric suction of the soil using predetermined calibration curve for the filter paper. The moisture distribution between the paper and soil sample depends on the pore-size of the papers. The calibration curves vary from paper to paper.

Whatman #42, Schleicher and Schuell #589, White Ribbon, and Fisher 9-790A are the most commonly used types of papers filter papers for suction measurement. Standard calibration curve for filter papers are either acquired or obtained by measuring the SWCC of representative papers using the pressure-plate or any commonly known techniques prior to the testing. This measurement is accomplished in the similar manner the soil specimens are tested. Alternatively, the papers may be brought in contact to the moist soil and the corresponding matric suction is measured using a tensiometers. Representative filter papers are initially oven-dried and then allowed to cool to room temperature in desiccators prior to the suction measurement of soil samples. In situ measurement of matric suction measurements using the contact filter paper method is less commonly used in geotechnical application, albeit the technique is simpler and cheaper to other methods of testing.