Delayed operative fixation of acetabular fractures remains a major problem in many parts of the world. No previous studies have reported the effect of fixation delay on health-related quality of life (HRQOL). We aimed to investigate the effect of delayed operative fixation of acetabular fractures on health-related quality of life, EuroQol-5 Dimension questionnaire (EQ-5D), and other related outcomes. We retrospectively analysed 117 patients who underwent open reduction internal fixation for displaced acetabular fractures between 2014 and 2021. Patients were divided into groups based on the admission-to-surgery time (interval between injury and definitive surgery): 1-14, 15-21, and >21days. Patients were analysed for associations between admission-to-surgery time and postoperative outcomes, including operative time, estimated blood loss, blood transfusion, postoperative complication, and quality of reduction. Eighty-five patients with a mean follow-up time of 3.94 ± 1.84years were analysed for the association between admission-to-surgery time and conversion to total hip arthroplasty, the Modified Merle d'Aubigné and Postel score, EQ-5D score, ability to sit cross-legged, and ability to sit squat. Multivariable linear regression was used for continuous outcomes and logistic regression for categorical outcomes associated with delayed operative fixation. An admission-to-surgery time > 14days was associated with significantly higher blood loss [785mL (236-1335), p = 0.006]. For associated fractures, an admission-to-surgery time > 21days increased the risk of poor reduction [odds ratio (OR), 5.21 (1.42-19.11), p = 0.013]. Further, admission-to-surgery time > 21days was associated with poor Modified Merle d'Aubigné and Postel scores [OR, 8.46 (1.48-48.29), p = 0.016], EQ-5D pain domain [OR, 3.55 (1.15-11), p = 0.028], and EQ-5D usual activity domain [OR, 4.24 (1.28-14), p = 0.018]. Delayed operative fixation of acetabular fractures after 21days affected the functional outcomes and HRQOL, independent of the reduction status. Surgical interventions and patient referrals should occur at the earliest and within 21days from the time of injury. The online version contains supplementary material available at 10.1007/s43465-024-01163-x.