OBJECTIVE: Timely detection of glaucoma is key to preventing or delaying vision loss. This study aimed to assess whether the routine use of optical coherence tomography (OCT) by optometrists for detection of glaucomatous changes in the optic nerve and retina increased glaucoma referrals to ophthalmologists. DESIGN: This study was a retrospective review of routinely-collected electronic medical records of patients from a chain of 331 optometry practices in Australia. PARTICIPANTS: Electronic medical records were reviewed for every patient aged 18-99 years who attended an included practice between January 1 and July 31, 2019. METHODS: Odds of referral for glaucoma assessment were compared between practices performing OCT routinely on all patients (OCT practices, n=175) and without OCT (non-OCT practices, n=20). A subset of referrals were assessed by ophthalmologists to determine the false positive referral rate. MAIN OUTCOME MEASURES: The primary outcome measure of this study was referral to an ophthalmologist for glaucoma assessment. A secondary outcome was the rate of false positive referrals, analysed in a subset of patients referred for glaucoma assessment. RESULTS: Records from 994,461 patients (59% female) were included and 10,475 (1.1%) were referred for glaucoma assessment. Most referrals were associated with normal intraocular pressure (non-OCT practices: n=496, 66%; OCT practices: n=6,603, 68%). Referral for glaucoma was higher in OCT practices (n=9,719, 1.1%) compared to non-OCT practices (n=756, 0.8%, age-, gender- and location-adjusted odds ratio 1.39, 95% confidence interval 1.10-1.76). Of 318 referred patients (3%, all from OCT practices) for whom ophthalmologist feedback was available, 68 (21%) were considered not to have glaucoma. CONCLUSIONS: The routine use of OCT in optometric practice may lead to more timely glaucoma detection and prevention of avoidable vision loss.