Abstract Aim To analyse non-ST-elevation myocardial infarction (NSTEMI) care in the Netherlands and to identify modifiable factors to improve NSTEMI healthcare. Methods This retrospective cohort study analysed hospital and pharmacy claims data of all NSTEMI patients in the Netherlands in 2015. The effect of percutaneous coronary intervention (PCI) during hospitalisation on 1‑year mortality was investigated in the subcohort alive 4 days after NSTEMI. The effect of medical treatment on 1‑year mortality was assessed in the subcohort alive 30 days after NSTEMI. The effect of age, gender and co-morbidities was evaluated. PCI during hospitalisation was defined as PCI within 72 h after NSTEMI and optimal medical treatment was defined as the combined use of an aspirin species, P2Y 12 inhibitor, statin, beta-blocker and angiotensin converting enzyme inhibitor/angiotensin II receptor blocker, started within 30 days after NSTEMI. Results Data from 17,997 NSTEMI patients (age 69.6 (SD = 12.8) years, 64% male) were analysed. Of the patients alive 4 days after NSTEMI, 43% had a PCI during hospitalisation and 1‑year mortality was 10%. In the subcohort alive 30 days after NSTEMI, 47% of patients were receiving optimal medical treatment at 30 days and 1‑year mortality was 7%. PCI during hospitalisation (odds ratio (OR) 0.42; 95% confidence interval (CI) 0.37–0.48) and optimal medical treatment (OR 0.59; 95% CI 0.51–0.67) were associated with a lower 1‑year mortality. Conclusion In Dutch NSTEMI patients, use of PCI during hospitalisation and prescription of optimal medical treatment are modest. As both are independently associated with a lower 1‑year mortality, this study provides direction on how to improve the quality of NSTEMI healthcare in the Netherlands.