Long‐aliphatic‐segment polyamides were prepared based on hexamethylenediamine and α,ω‐(CH2)x biosynthetic diacids (x = 10, 11, 12). The pertinent monomers (salts) were isolated as solids, thoroughly characterized for the first time, and then submitted to an anhydrous melt prepolymerization technique. The obtained prepolymers exhibited $\overline {M} _{{\rm n}} $ in the range of 5 100–11 800 g · mol−1, and the molecular weight was further increased by up to 55% through solid‐state finishing. The suggested overall polyamidation cycle was conducted at short melt‐reaction times, so as to avoid any thermal degradation, and was proved efficient, indicating similar reactants polymerizability independently of the methylene content.magnified image