The dual antiplatelet therapy (DAPT) score was developed to identify patients undergoing percutaneous coronary intervention (PCI) who are likely to derive benefit (score ≥2) or harm (score <2) from extended DAPT beyond 1-year post-PCI with respect to ischaemic and bleeding outcomes. We examined the associations between DAPT score at index PCI and long-term mortality from an all-comers PCI registry in patients receiving DAPT as per the standard of care. We retrospectively examined prospectively collected data from the Melbourne Interventional Group PCI database (2005- 2018) and grouped patients as having DAPT score ≥2 or <2. Long-term mortality was assessed from the Australian National Death Index linkage. The primary endpoint was long-term mortality using survival analysis. Secondary endpoints included in-hospital events and 30-day major adverse cardiac events (MACE), a composite of death, myocardial infarction, or target vessel revascularization. Of 27,740 study patients, 9,402 (33.9%) had DAPT score ≥2. Patients with DAPT score ≥2 were younger and included more females with higher prevalence of cardiovascular risk factors. Patients with DAPT score ≥2 had higher in-hospital mortality (3.0% vs. 1.0%) and major bleeding (2.3% vs. 1.6%), 30-day MACE (7.1% vs. 3.1%), and long-term mortality at a median follow-up of 5.17 years (21.9% vs. 16.5%), p<0.001 for all. A third of all-comer patients undergoing PCI had a DAPT score ≥2 with greater short-term ischaemic and bleeding risk, and higher long-term mortality. Risk assessment using the DAPT score may guide the duration and intensity of DAPT beyond the early post-PCI period.