An ultrahigh vacuum (UHV) scanning tunneling microscopy/spectroscopy (STM/STS) system was used to study the density of states of Til+xS2 (0.090 greater than or equal to x greater than or equal to 0.002) near the Fermi lever (E(F)). The effect of excess Ti on the local band structure and the position of E(F) was investigated. The Til+xS2 single crystals studied were prepared by sulfur transport and cleaved under UHV conditions prior to in situ UHV STM/STS investigations. No new features or major changes were observed in the normalized conductance, (dI/dV)/(I/V), as a function of x. The band-gap energy of 0.5 +/- 0.1 eV was essentially composition independent. These results can be explained within the rigid-band model, with electrons from the intercalated Ti being donated to the host conduction band. It has been demonstrated that STM/STS is a very sensitive atomic-level surface probe of intercalation charge transfer, especially for x less than or equal to 0.05. Direct measurements of the E(F) shift can provide a semiquantitative measure of charge transfer to the external basal planes. These unique capabilities of STS can be used to probe the roles of adsorbate and guest-host charge transfer during intercalation at an unprecedented level of resolution.