Wetting and transport properties of cotton assemblies including fibers, yarns, and woven structures were studied using an experimental protocol and a data decoupling technique developed for the simultaneous measurement of such properties in porous materials. The effects of alkaline scouring on water wetting and retention properties of cotton assemblies were investigated. The effectiveness of scouring in improving water wetting properties depends on the forms of the cotton assemblies on which scouring is performed, i.e., slivers, yarns, and fabrics. Correlations between wetting and liquid retention properties were demonstrated. This experimental approach provides an effective tool for detecting surface modification of cotton assemblies and its effect on liquid wetting and retention properties.