Background: Elderly patients receive bare metal stents instead of drug-eluting stents (DES) to shorten the duration of dual antiplatelet therapy (DAPT). The SENIOR trial compared outcomes between these 2 types of stents combined with a short duration of DAPT. A significant decrease in the number of patients with at least 1 major adverse cardiac and cerebrovascular event (MACCE) was noted in the DES group. Objectives: The objective of this article was to perform an economic evaluation of the SENIOR trial. Methods: This evaluation was performed separately in 5 participating countries using pooled patient-level data from all study patients and country-specific unit costs and utility values. Costs, MACCEs, and quality-adjusted life-years (QALYs) were calculated in both arms at 1 year, and an incremental cost-effectiveness ratio was estimated. Uncertainty was explored by probabilistic bootstrapping. Results: A total of 1200 patients underwent randomization. The average total cost per patient was higher in the DES group. The number of MACCEs and average QALYs were not statistically different between the 2 groups. The 1-year incremental cost-effectiveness ratio for each country of reference ranged from €13 752 to €20 511/MACCE avoided and from €42 835 to €68 231/QALY gained. The scatter plots found a wide dispersion, reflecting a large uncertainty surrounding the results. But in each country studied, 90% of the bootstrap replications indicated a higher cost for greater effectiveness for the DES group. Assuming a willingness to pay of €50 000/QALY, there was between a 40% and 50% chance that the use of DES was cost-effective in 4 countries. Conclusion: The use of DES instead of bare metal stents combined with a short duration of DAPT in elderly patients induced higher cost for greater effectiveness in each of the 5 countries studied.