Abstract <p>The work investigates the thermoelectric effect in mixtures of colloidal solutions with ionic electrolytes in the initial state, when the formation of concentration gradients under the influence of an inhomogeneous temperature field can be neglected. Based on experimental measurements in mixtures with different concentrations of colloidal particles and ions, the conditions under which with the coefficient of thermoelectric electromotive force (EMF) is governed by the ionic subsystem and when the main contribution to the value of the thermoelectric EMF is made by colloidal particles are determined.</p>