In this work, efficient solid acid catalysts were obtained from the stoichiometric reactions of Keggin heteropolyacids with SnSO4 and evaluated in the etherification reactions of glycerol with tert-butyl alcohol (TBA). Among the salts synthesized, the Sn2SiW12O40 catalyst was the most active and selective toward glyceryl ethers. High yields of mono- and diglyceryl tert-butyl ethers were achieved after 4 h of reaction at 393 K. The impacts of the main reaction parameters such as stoichiometry of the reactants, catalyst load, time, and reaction temperature were assessed. The efficiency of the Sn2SiW12O40 catalyst was also assessed in etherification reactions of ethylene glycol with TBA, and etherification reactions of glycerol with other alcohols (i.e., n- or sec-butyl alcohol, and n- or iso-propyl alcohol). A proposal that describes the reaction pathway including the catalyst participation was also described.