Importance Intravitreal complement inhibitors injections (IVCIs) slowed progression of geographic atrophy (GA) lesions in several registration phase 3 trials although without benefit for prespecified secondary functional vision outcomes. Patient acceptability of these therapies needs further exploration. Objective To quantify the acceptability of IVCI therapy to United Kingdom patients with GA, assuming vision outcome benefits are expected. Design, Setting, and Participants This cross-sectional study took place at 9 geographically dispersed UK National Health Service centers from April 2023 to April 2024 among 153 participants with treatment-naive GA in at least 1 eye. Exposures GA in at least 1 eye. Main Outcomes and Measures Main outcomes were (1) acceptability of IVCI therapy based on completion of validated acceptability questionnaire. Participants were provided with a treatment information leaflet coproduced by a patients with lived experience of GA to inform them about the risks and benefits of IVCI for GA, assuming there were vision outcome benefits to this treatment and (2) response to the EuroQol 5-dimension with a vision bolt-on questionnaire to assess general health and vision-related quality of life. Spearman rank correlations and χ 2 tests were used to explore associations between acceptability levels and specific ocular and sociodemographic characteristics. Results A total of 153 participants were recruited (93 [60%] women; mean [SD] age, 82 [7]), 57 (38%) of whom had bilateral foveal involvement. Median (IQR) visual acuity with habitual correction in the better-seeing eye and in eyes where neither eye was better or worse was logMAR, 0.30 (0.14-0.54; approximate Snellen equivalent, 20/40) and 0.47 (0.14-0.84; approximate Snellen equivalent, 20/63), respectively. Among the 153 participants, 81 (53%; 95% CI, 45-61) reported IVCIs were very much or extremely acceptable under the theoretical scenarios provided. The proportion finding IVCIs acceptable rose to 82% (95% CI, 76-88) when including those who rated prospective treatment as moderately acceptable. Belief in the perceived effectiveness of the treatment (ρ, 0.52; 95% CI, 0.40-0.63; P &lt; .001) and confidence in their ability to attend the eye clinic regularly (ρ, 0.51; 95% CI, 0.38-0.62; P &lt; .001) correlated with overall acceptability. Conclusions and Relevance IVCI therapy for GA may be acceptable to most UK patients with GA under the assumption that there are vision outcome benefits to this treatment. While current treatments do not result in vision outcome benefits, perceived effectiveness by patients was associated with acceptability, emphasizing the desire to quantify vision functional benefit concomitant with anatomical slowing of progression.