We assessed the performance of the newly fitted Sage force field in relative binding free energy calculations. The Parsley results were compared to previously published results using the GAFF2.1x/AM1-BCC, and OPLS3e 9,112 force fields. We specify the force field as "GAFF2.1x" as results across the dataset are pulled from two different studies, with some systems using GAFF2.1, and a later study using GAFF2.11. Specific systems using each force field version are listed in the SI in Table . The GAFF2.1x/AM1-BCC calculations results were calculated with the same pmx workflow for both Sage and Parsley, and the OPLS3e results were calculated with Schrödinger FEP+. The test set consisted of 22 different series of congeneric ligands binding to 20 protein targets with a total of 599 ligands.