<p>In earthquake-prone regions, the accumulation of geophysical stress during the aseismic period plays a critical role in determining which faults are more likely to be reactivated in future seismic events. However, a clear understanding of how non-planar fault geometry influences aseismic stress buildup is still lacking. This study examines how non-planar fault affect displacement, stress, and strain evolution in a viscoelastic medium during the aseismic period. We model an infinite non-planar fault composed of three interconnected planar segments embedded in a viscoelastic half-space represented by a fractional Maxwell medium. The problem is formulated as a two-dimensional boundary value problem and solved numerically using a Laplace transformation, fractional derivative, correspondence principle and Green’s function technique. The outcomes are demonstrated graphically using appropriate model parameters. The computational findings highlight the significant influence of fault motion and geometry in shaping the displacement, stress and strain fields in the vicinity of the fault zone. A comparative analysis with existing theoretical models is also performed to validate the results and highlight the impact of fractional derivatives on the response. These results can provide insights into subsurface deformation and its impact on fault movement, which may contribute to the study of earthquake activity.</p>