Silver iodide (AgI) is a well‐established ice-nucleating agent widely employed in cloud seeding, yet the precise mechanism governing its efficiency remains elusive. Noncontact atomic force microscopy (nc-AFM) revealed that the Ag-terminated (0001) surface forms a (2 × 2) reconstruction with ordered Ag vacancies, preserving a hexagonal arrangement suitable for epitaxial growth of ice. In contrast, the I-terminated (0001) surface exhibits a complex rectangular reconstruction that hinders epitaxial ice formation. These experimental results indicate that the Ag-terminated basal plane is primarily respon- sible for effective ice nucleation on silver iodide [1]. Computational modeling of AgI has significant limitations because of the highly polarizable silver and iodine ions and the crucial role of van der Waals interactions, which are often poorly described by standard theoretical methods [2]. Our density functional theory (DFT) calculations showed strong sensitivity to the choice of the exchange- correlation functional, often failing to reproduce the experimental AgI lattice parameters accurately. Conversely, advanced (and computationally expensive) ab-initio calculations using the random phase approximation (RPA) provided excellent agreement with the experimental bulk properties and al- lowed us to obtain reliable structure models. AFM simulations using the Probe-Particle Model [3] reproduced the experimental observations. Based on this benchmark, we discovered that the PBE-D3 functional [4] can be a valid alternative for computationally efficient simulations of the AgI/water interface. Our findings highlight the decisive role of employing advanced computational methods for the structure determination of systems containing highly polarizable atoms.