Abstract Polar oil additives are able to substantially improve the solubilization in surfactant‐oil‐water microemulsions through the so‐called lipophilic linker effect. Long‐chain alcohols (above C 8 ) and their low ethoxylation derivatives were found to produce such an improvement. A method is proposed to evaluate the lipophilic linker performance and to compare lipophilic linker candidates in different oil‐surfactant systems. The best lipophilic linker was found to have a hydrophobe chain length as an average between that of the surfactant tail and the n ‐alkane oil. The experimental data agree with that obtained by using a simple model based on the estimation of molecular interactions.