This study investigated patient and operative characteristics for immediate sequential bilateral cataract surgery (ISBCS) and delayed bilateral cataract surgery (DSCS). The annual NHS spend on cataract surgery is £500 million, a figure expected to rise by 50% in the next 20 years. In the absence of substantial changes to NHS practices, rationing of cataract surgery will be inevitable. National Institute of Health & Care Excellence (NICE) suggests consideration of ISBCS to two groups of patients: “those with low risk of ocular complications during and after surgery” and “those who need general anaesthesia, but for whom this poses an increased risk of complications or distress”. Data were analysed from the Royal College of Ophthalmologists’ National Ophthalmology Database Audit (NOD) of cataract surgery. Between 2010-2019, 1073 (0.4%) patients had ISBCS and 248,341 (96.6%) had DSCS from 73 centres. More ISBCS cases were unable to lie flat (11.3% vs. 1.8%), more were unable to cooperate during surgery (9.7% vs. 2.7%), more had count fingers visual acuity (CF VA) or worse (23.4% vs. 5.0%) and more had general anaesthesia (58.7% vs. 6.6%) compared with DSCS. More ISBCS cases had mature cataracts (14.9% vs. 3.3%), no fundal view (6.6% vs. 0.8%), and intraoperative complications (3.5% vs. 2.6%) compared with DSCS eyes. Case-complexity adjusted polymerase chain reaction (PCR) rate was 0.98% for ISBCS and 0.78% for DSCS eyes. There were no endophthalmitis cases in the ISBCS cohort and 53 (0.01%) for the DSCS group. In summary, within the NHS, ISBCS is being performed on a small number of high complexity patients. The NICE defined cohort of patients at “low risk of ocular complications” are either not being offered this surgical option, or are universally declining it. Two recent national surveys of lead cataract clinicians found that none was offering ISBCS routinely. The unsubstantiated perception of absence of benefit to patients, combined with the perception of increased risk of bilateral complications may remain as insurmountable barriers to widespread adoption, unless better evidence is generated to inform the debate.