<p>Heterovalent doping of ferroelectric materials is a fundamental tool to optimize their properties. In ZrO₂ and HfO₂-based materials, La doping has proven particularly effective in stabilizing the polar orthorhombic (o-) phase and in enhancing the overall ferroelectric properties. However, a full understanding of the effects of doping and associated charge compensation on ferroelectric properties is still lacking. In this work, we use first-principles density functional theory (DFT) calculations to explore how configurational disorder and charge compensation affect the FE properties and switching of orthorhombic La:ZrO₂. We found an intrinsic preference for ionic compensation, leading to the spontaneous formation of oxygen vacancies. Both the charge compensation mechanism and the spatial configuration of dopants significantly influence the spontaneous polarization and piezoelectric response of the material. Furthermore, we show that the La spatial distribution governs the favorable sites for oxygen vacancy formation. The resulting La–V_O–La defect complexes introduce strong asymmetries in the energies between polar states and switching barriers, pointing to a potential microscopic contribution to domain pinning. This work unravels the complex interplay between doping, charge compensation and FE properties in ZrO₂ films.</p>