Phase-field approaches have become a well-established and powerful framework for modeling the initiation and evolution of drying-induced fractures in variably saturated porous media [1–5]. In this contribution, a thermo–hydro–mechanical phase-field model is developed and validated for the investigation of crack nucleation and propagation driven by coupled thermal, hydraulic, and mechanical processes in multiphase porous materials. Building upon previous studies ([1–3]), the proposed formulation extends the description of fracture in deformable, variably saturated porous media by incorporating heat transfer, liquid water and gas flow. The predictive capabilities of the model are demonstrated through a series of numerical examples, including mechanical, hydro-mechanical, and fully thermo–hydro–mechanical fracture scenarios. In particular, simulations such as thermal shock loading and coupled thermo-hydraulic drying-induced cracking illustrate the significant role of thermal effects on crack initiation, propagation, and interaction with desaturation processes. The results provide further insight into the complex coupling between heat transfer, moisture transport, and fracture mechanics in porous media.