To identify anatomic determinants of reading performance in eyes with foveal-sparing geographic atrophy (GA). Prospectively recruited, cross-sectional study, SIGHT (clinicaltrials.gov identifier, NCT02332343). Patients with foveal-sparing GA secondary to age-related macular degeneration (AMD). 2.4 lines in the smallest readable print size of an individual eye, was computed. The status of the M3R was determined as either free of atrophy or involved in the atrophic process, and the impact on reading was assessed. Radner reading score (logRAD) and reading speed (words per minute [wpm]). +73.08 wpm [IQR, 27.43-86.64 wpm] compared with the largest test sentence). The results indicate that a defined area on the retina that can be assessed by retinal imaging is required for unhindered reading in patients with foveal-sparing GA. The findings highlight that smaller test sentences can be read faster by patients with this AMD subphenotype. Our results allow prediction of reading impairment based on imaging parameters in clinical routine and may support establishing anatomic surrogate end points in clinical trials. Furthermore, the findings could be used to facilitate the adjustment of magnifying reading aids.