Two-component solventless polyurethane adhesive compositions comprising an isocyanate component and an isocyanate-reactive are disclosed, the compositions comprising an isocyanate component comprising an isocyanate-terminated prepolymer and an isocyanate-reactive component comprising a hydroxy-terminated polyurethane resin, a polyether polyol, a phosphate ester adhesion promoter, and, optionally, a bio-based polyol. Methods for forming laminate structures are also disclosed, the methods comprising forming an adhesive composition by mixing an isocyanate adhesive component comprising an isocyanate-terminated prepolymer and an isocyanate-reactive adhesive component comprising a hydroxy-terminated polyurethane resin, a polyether polyol, a phosphate ester adhesion promoter, and optionally, a bio-based polyol, applying the adhesive composition to a surface of a first substrate, and bringing a surface of a second substrate into contact with the adhesive composition on the surface of the first substrate, thereby forming the laminate structure. Laminate structures are also disclosed.