Abstract Background To assess the association between variation in retinal central subfield thickness (CSFT) with best‐corrected visual acuity (BCVA) change in patients receiving vascular endothelial growth factor (VEGF) inhibitor therapy for neovascular age‐related macular degeneration (nAMD). Methods CSFT measurements were obtained from 141 eyes (total 1300 scans). SD of CSFT was calculated. The eyes were categorised into CSFT variation tertiles. Multiple linear regression was used to examine the association between the CSFT tertiles and BCVA change at 12 mo, adjusting for differences in baseline demographic and clinical characteristics. Results At 12 mo, the mean BCVA of the high CSFT variation group (50.6 letters) was significantly lower than the low and moderate CSFT variation groups (57.5 and 59.8 letters, respectively), P = .02. The adjusted mean BCVA gains were +1.7, +7.2, and +7.8 letters in the high, moderate and low CSFT variation groups, respectively ( P = .03). Conclusions A greater variation in retinal thickness during VEGF inhibitor therapy for nAMD is associated with a less favourable visual outcome. CSFT stability is useful in prognosticating visual outcomes in VEGF inhibitor therapy for nAMD.