3-Alkylphenols derived from renewable natural resources have been used to synthesise thiobisphenols by reaction with sulfur dichloride. In contrast to previous work, we have found that 3-alkylphenols give isomeric products, the major symmetrical, the 4,4′-thiobis compound, the minor symmetrical, 2,2′-thiobisphenol, and some of the believed unsymmetrical isomer. The role of the solvent and catalyst have been studied in the reaction of 3-pentadecylphenol with sulfur dichloride. Evidence for the structures of the 2,2′ and 4,4′ isomers has been obtained from related reactions of 4-bromo-3-methylphenol, 2-bromo-5-methylphenol and their chloro analogues.