By optimizing the growth conditions and doping with Bi, we have produced epitaxial layers of SnTe with hole concentration as low as 2.6×1018 cm−3. This is more than an order of magnitude less than the smallest carrier concentration reported for undoped bulk crystals (even with heat treatment to reduce the metal vacancy concentration). The hole mobility is found to depend somewhat on the Bi content. Measurements of the refractive index of low carrier concentration SnTe show very little dispersion for wavelengths up to 30 μm.