Synchrotron radiation photoemission spectroscopy is used to study the electronic structure and growth mechanisms of Sn on cleaved GaAs(110) surfaces. Detailed core‐level analysis, along with the substrate intensity attenuation and valence‐band information, indicate that Sn forms nondisruptive bilayer patches on cleaved GaAs(110) surface for coverage θ between 0≤θ≤ 1 monolayer (ML). In the 1<θ<2.5 ML coverage range, the bilayer growth atop the substrate is accompanied by the initial growth of Sn‐based structures on top of the bilayer. The bilayer and Sn‐based structures are semiconducting. The substrate is completely covered at ∼2.5 ML. Continued deposition above 2.5 ML results in Sn clusters. A Sn‐induced density of states progressively fill in the region between the valence‐band maximum (VBM) and the Fermi level (EF) with Sn deposition. At coverages above 3 ML, Sn derived states show emission atEF. The electronic structure changes during the interface development leads to the continuous band bending towards midgap. The total amount of band bending at 8 ML is about 0.67 eV.