Solvent-based polyurethanes and poly(urethane-acrylate)s were synthesized using phosphorus-containing polyester polyols in order to compare the thermal properties of different polymer types. Since the location of the phosphorus group might have vital importance when comparing the thermal properties, phosphorus groups were kept on the pendant chains in poly(urethane-acrylate)s using phosphorus-containing urethane macromonomers while they were kept on the backbone in polyurethanes. The effect of molar mass of polyurethanes and pendant urethane chains of poly(urethane-acrylate)s on thermal properties was also investigated. Characterization of the synthesized polymers was carried out using FT-IR, GPC, NMR, and DSC followed by evaluation of the thermal properties.