An integral bridge is a structural system characterized by the monolithic casting of both superstructure and substructure, eliminating the need for expansion joints and bearings. The absence of such elements in integral bridges results in reduced maintenance costs compared to conventional bridges, which often face issues such as water leakage and bearing replacements. However, the response of integral bridges is sensitive to temperature variations, requiring the design to incorporate thermal expansion/contraction and ensure that stresses remain within acceptable limits. The thermal stresses in integral bridges depend significantly on the strength and stiffness of the abutment infill. Therefore, when estimating thermal stresses, it is crucial to consider soil-structure interaction. Additionally, integral bridges may be subjected to design earthquakes in conjunction with thermal stresses, as these thermal stresses are seasonal. The present study focuses on understanding the behaviour of integral bridges (IB) under thermal variations and seismic loads. A numerical model of an integral bridge has been developed, including the superstructure, substructure, and surrounding soil. Nonlinear soil-structure interaction is considered in modelling abutment-soil and pile-soil interactions. Initially, the bridge is subjected to self-weight and thermal loading, followed by the application of seismic loads on the stressed structure. The combined effect of thermal and seismic loads has been evaluated, taking into account various key structural and soil parameters.