Measurements of the surface state distribution and of the fixed surface charge of a hydrogen terminated Si(111) surface are reported. The investigations were carried out by the large signal surface photovoltage technique. The electronic properties of the electrolytically prepared n-Si(111) surface are compared after storage in nitrogen and in air and after hot water oxidation. The surface state distribution of the hydrogen-terminated Si(111) surface exposed to N-2 is nearly intrinsic, and the density of states at midgap is 1.7.10(11) eV(-1) cm(-2). The exposure to air induces extrinsic surface states in the midgap region of the distribution.