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The shallow 1971 MW 6.6 San Fernando, California earthquake involved a complex rupture process on an immature thrust fault with a non‐planar geometry, and is notable for having a higher component of left‐lateral surface slip than expected from seismic source models. We extract its 3‐D coseismic surface displacement field from aerial stereo photographs and document the amount and width of the vertical and fault trace‐parallel components of distributed deformation along strike. The results confirm the significant left‐lateral surface offsets, suggesting a slip vector rotation at shallow depths. Comparing our offsets against field measurements of fault slip, we observe that most of the offset was accommodated in the damage zone, with off‐fault deformation averaging 69% in both the fault trace‐parallel and vertical components. However, the magnitude and width of off‐fault deformation behave differently between the vertical and fault trace‐parallel components, which, along with the rotation in rake near the surface, can be explained by dynamic rupture effects. Plain Language Summary: The 1971 San Fernando, California earthquake is infamous for its strong ground motions and large lateral fault offsets measured in the field, despite the compressional tectonic stresses that triggered the earthquake. We produce maps of the 3‐D surface deformation that occurred during the earthquake by comparing pre‐earthquake and post‐earthquake aerial photographs of this area. The results confirm the presence of important lateral and compression‐driven deformation at the surface. This surface deformation was distributed over a wide zone, and as such, previously reported field measurements did not capture the total slip that occurred at the surface. Understanding controls on the width of the deformation zone provides insight into earthquake behavior and helps improve our estimates of seismic hazard. Our results show that during the San Fernando earthquake, lateral and compression‐driven deformation behaved differently within the fault zone, which may suggest that the two slip components were affected by different factors and damage generation mechanisms. Key Points: Correlation of aerial photographs reveals significant left‐lateral surface deformation in the 1971 San Fernando earthquakeOff‐fault deformation is partitioned between the fault trace‐parallel and vertical components of deformationPrimary controls of off‐fault deformation may be different for the fault trace‐parallel and vertical components [ABSTRACT FROM AUTHOR]