Importance: Drug coupons are widely used, but their effects are not well understood. Objective: To quantify the effect of coupons on statin use and expenditures. Design: Retrospective cohort analysis of IMS Health LRx LifeLink database. Setting: U.S. retail pharmacy transactions. Participants: Incident statin users who initiated branded atorvastatin or rosuvastatin between June 2006 and February 2013. Main Outcomes and Measures: Monthly statin utilization (pill-days of therapy), switching (filling a different statin), termination (failure to refill statin for 6 mo), and out-of-pocket and total costs. Results: Of 1.1 million incident atorvastatin and rosuvastatin users, 2% used a coupon for at least one statin fill. At 1 year, compared with noncoupon users, those who used a statin coupon on their first fill were dispensed an equal number of monthly pill-days (23.7 vs 23.8), were less likely to switch statins (14.4% vs 16.3%), and were less likely to have terminated statin therapy (31.3% vs 39.2%). At 4 years, coupon users were more likely to have switched (45.5% vs 40.8%) and less likely to have terminated statin therapy (50.6% vs 61.1%) compared with noncoupon users. Those who used greater numbers of coupons were substantially less likely to switch and terminate statin therapies. Monthly out-of-pocket costs were lower among coupon than noncoupon users at 1 year ($9.7 vs $15.1), but total monthly costs were qualitatively similar ($115.5 vs $116.9). At 4 years, monthly out-of-pocket costs among coupon users remained lower ($14.3 vs $16.6) compared with noncoupon users. Sensitivity analyses supported the main results. Conclusions: Coupons for branded statins are associated with higher utilization and lower rates of discontinuation and short-term switching to other statin products.