The self-metathesis of erucic acid with ruthenium-based catalysts, followed by the hydrogenation of the double bond, yielded 1,26-hexacosanedioic acid (AA). Polycondensation of this biobased long-chain α,ω-dicarboxylic acid with hexacosane-1,26-diol (BB), generated from the former by reduction, yielded the polyester 26,26. Monomer AA was also polymerized with short-chain alkanediols, namely dodecane-1,12-diol and butane-1,4-diol, generating polyesters 12,26 and 4,26, respectively. The properties of these aliphatic polyesters were investigated by various techniques, revealing high crystallinity, melting, and degradation temperatures, depending on the monomers used. These materials are an attractive alternative to fossil resource-based polymeric materials.