On GOES 16–19, the primary instrument for measuring solar- and galactic-origin energetic protons is the Solar and Galactic Proton Sensor (SGPS). Each satellite carries two SGPSs, one looking eastward and one looking westward in; the orbit. Each SGPS measures proton fluxes in 13 differential energy channels spanning approximately 1–500 MeV and a single >500 MeV integral channel. This paper focuses on the characterization of the two SGPS channels that ; overlap with the >300 MeV to >433 MeV proton energy response of neutron monitors in the polar regions. Although the SGPS differential channels are primarily aimed at measuring solar energetic particle (SEP) fluxes, the P11 ; (>500 MeV) integral channel was designed to measure both galactic cosmic rays (GCRs) and the high energy component of SEP events. The P10 (275��500 MeV) channel also measures both GCRs and SEPs. Special care is needed in ; processing the P10 and P11 channels to obtain an accurate spectrum at energies >300 MeV. A bowtie analysis of the response functions using realistic SEP and GCR spectra gives different geometric factors and effective ; energies for the two populations.