BACKGROUND: The Timing of Intervention in Acute Coronary Syndromes (TIMACS) trial demonstrated that early invasive intervention (within 24 hours) was similar to a delayed approach (after 36 hours) overall but improved outcomes were seen in patients at high risk. However, the cost implications of an early versus delayed invasive strategy are unknown. METHODS AND RESULTS: A third-party perspective of direct cost was chosen and United States Medicare costs were calculated using average diagnosis related grouping (DRG) units. Direct medical costs included those of the index hospitalization (including clinical, procedural and hospital stay costs) as well as major adverse cardiac events during 6 months of follow-up. Sensitivity and sub-group analyses were performed. The average total cost per patient in the early intervention group was lower compared with the delayed intervention group (-$1170; 95% CI -$2542 to $202). From the bootstrap analysis (5000 replications), the early invasive approach was associated with both lower costs and better clinical outcomes regarding death/myocardial infarction (MI)/stroke in 95.1% of the cases (dominant strategy). In high-risk patients (GRACE score ≥141), the net reduction in cost was greatest (-$3720; 95% CI -$6270 to -$1170). Bootstrap analysis revealed 99.8% of cases were associated with both lower costs and better clinical outcomes (death/MI/stroke). LIMITATIONS: We were unable to evaluate the effect of community care and investigations without hospitalization (office visits, non-invasive testing, etc). Medication costs were not captured. Indirect costs such as loss of productivity and family care were not included. CONCLUSIONS: An early invasive management strategy is as effective as a delayed approach and is likely to be less costly in most patients with acute coronary syndromes.