Abstract Background Contemporary studies have demonstrated that in non-ST-segment elevation myocardial infarction (NSTEMI), processes of care vary significantly according to biological sex. Little is known regarding variation in practice between geographical areas and individual centers. Methods & Results We identified 305,014 admissions with NSTEMI in the United Kingdom (UK) Myocardial Infarction National Audit Project (MINAP), 2010-2017, including female sex (n = 110,209). Females presented significantly older (77y vs. 69y, P<0.001), were more likely to be Caucasian (93% vs. 91%, P<0.001) and less likely to be current smokers (18% vs. 24%, P<0.001). Females were less frequently treated with GDMT after NSTEMI, less frequently managed with an invasive coronary angiogram (ICA) (58% vs. 75%, P<0.001) during index admission and less frequently underwent PCI (35% vs. 49%, P<0.001) or CABG surgery (5% vs. 9%, P<0.001) compared to males. Structural process of care differed between the sexes, with a lower proportion of females being treated on a dedicated cardiology ward (48% vs. 56%, P<0.001) or admitted under a attending cardiologist (44% vs. 52%, P<0.001). In our hospital-clustered analysis, we show a positive correlation between the risk-standardized mortality rates (RSMR) and increasing proportion of women treated for NSTEMI (R2=0.17, P<0.001). There was a clear negative correlation between the proportion of females who had an optimum opportunity-based quality indicator score (surrogate for optimum process of care) during their admission and RSMR (R2 =0.22, P<0.001), with a far weaker correlation in males (R2 =0.08, P<0.001). Conclusion There was a significant in variation of the management of patients with NSTEMI according to sex, with widespread geographical variation. Structural changes are likely required to enable successful change for female patients.