The move guarantees that Peat will earn $9.625 in 2019, according to the Times-Picayune of New Orleans.
A first-round draft pick (No. 13 overall) of the Saints in 2015, Peat has started 37 of 42 games in his three seasons in New Orleans, including 14 in 2017.
The Saints featured the league's fifth-ranked running attack last season behind the tandem of Mark Ingram and rookie Alvin Kamara, averaging 129.4 yards rushing.
The 6-foot-7, 312-pound Peat suffered a broken fibula in the Saints' wild-card matchup against Carolina, but he is expected to be ready in time for the start of training camp.