A black-and-white photothermographic material that is sensitive at a wavelength greater than 700 nm, and comprises a support having thereon one or more thermally-developable imaging layers comprising a binder and in reactive association, a photosensitive silver halide, a non-photosensitive source of reducible silver ions, and a reducing composition for the non-photosensitive source reducible silver ions. The thermally-developable layers further comprises one or more indolenine dyes as post-processing stabilizing compounds and one or more merocyanine dyes or cyanine spectral sensitizing dyes that comprise one or more thioalkyl, thioaryl, or thioether groups.