One-component, H-siloxane-containing addition-crosslinkable silicone resins, are prepared by charging a reactor with water and a solvent mixture of at least one aromatic solvent and at least one alkyl ester, adding a chlorosilane mixture containing an Si—H functional silane and a silane bearing an unsaturated hydrosilylatable group with stirring, the temperature not being above 50° C., separating an aqueous phase comprising a one-component, H-siloxane-containing addition-crosslinkable silicone resin, and washing the phase comprising the one-component, H-siloxane-containing addition-crosslinkable silicone resin in at least two washing steps to reduce residual HCl content, a final washing carried out using a 0.01%-1.0% strength aqueous solution of a base with a pH between 7.00-8.50, at a temperature of 20-50° C.