We report on current-induced spin–orbit torques and field-free magnetization switching in a two-dimensional van der Waals heterostructure consisting of ${\text{WTe}}_2$ as the spin source and ${\mathrm{Fe}}_3{\mathrm{GeTe}}_2$ as the magnetic layer. Harmonic magneto-optical Kerr effect measurements enable the disentanglement of torque components arising from out-of-plane and in-plane spin accumulations generated by charge transport in ${\text{WTe}}_2$. Our analysis reveals a dominant contribution from out-of-plane spins, yielding a field-like torque efficiency of approximately $8.8\%$, and a damping-like torque efficiency arising from in-plane spins of $1.8\%$ at $150\mathrm{K}$. We observe deterministic bipolar field-free switching of the perpendicular magnetization of ${\mathrm{Fe}}_3{\mathrm{GeTe}}_2$ up to the Curie temperature, consistent with the strong torque generated by out-of-plane spins. The switching efficiencies extracted from current-induced magnetization reversal and hysteresis loop shifts exceed the intrinsic torque efficiencies measured by harmonic magneto-optical Kerr effect by more than one order of magnitude. The switching efficiencies scale with the temperature-dependent coercivity of the ${\mathrm{Fe}}_3{\mathrm{GeTe}}_2$ flake, indicating that they reflect a combination of thermal effects assisting magnetization reversal and different torque components. Our results provide a quantitative assessment of unconventional spin–orbit torques in ${\mathrm{Fe}}_3{\mathrm{GeTe}}_2/{\text{WTe}}_2$ and emphasize the importance of carefully interpreting torque efficiencies derived from switching-based measurements, particularly in van der Waals systems with Curie temperatures near or below room temperature.

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• Magnetization switching
• Magneto-optical Kerr effect
• Spin-orbit torque
• Spintronics
• van der Waals systems