The properties of resins determine their function in solid-phase peptide synthesis (SPPS) and play a key role in the outcome of a synthesis. Precise microwave heating has emerged as a very valuable tool in SPPS. We have systematically compared several commercially available resins, including Tentagel, ChemMatrix, PEGA and polystyrenes, for use in SPPS with microwave heating. We compared both the synthesis of short, difficult sequences and long sequences. The peptides were synthesized on these supports using a Biotage® Syro Wave™ synthesis robot with microwave heating during the coupling step, i.e. amide bond formation. The evaluation was based not only on purity of the crude products but also on the yields. Resins for solid-phase synthesis have generally been developed for applications at ambient temperature. Our results indicate that the improved synthesis conditions provided by microwave heating often will allow the use of basic, less expensive solid supports.