Polygrammodes croesus is a moth in the Crambidae family. It was described by Druce in 1895. It is found in Guatemala. The fore- and hindwings are chrome-yellow, shaded with blackish-grey scales at the base and across the middle, crossed from the costal to the inner margin by two curved dark grey lines. There is a rather faint submarginal zigzag line extending from the costal margin near the apex to the inner margin of the forewings and there is a small round spot at the base of the cell. There is an elongate hyaline-white spot at the end. The hindwings have a hyaline-white spot at the end of the cell.