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Transfer of <2 µm soil particles is a key process in the dispersion of pollutants and the textural differentiation of soil. Dispersion tests involving low-energy water-dispersible clay (LEWDC) are commonly used to indicate the stock of particles <2 µm that can be mobilized. However, notable differences in LEWDC protocols exist. We discuss the impact of the initial soil matrix potential on the dispersion sensitivity of <2 µm particles and the nature (mineralogy and particle size) of the dispersed particles. The dispersion sensitivity was more differentiated among soils with a high initial water content, which allows better soil discrimination. The nature of dispersed <2 µm particles was closer to that of the bulk <2 µm soil when moist initial conditions are considered, whereas enrichment in coarse clay minerals (with a particle size mode around 2 µm) was observed with dry initial conditions. Performing the LEWDC test under both moist and dry initial conditions can be used to interpret soil functioning. Abbreviations: LEWDC: low-energy water-dispersible clay Highlights-Moist initial condition allows better discrimination of particle dispersion among soils-Nature of dispersed <2 µm particles varies with the initial soil matrix condition-LEWDC test at two different initial conditions allows soil functioning analysis