IMPORTANCE: Pay for performance is intended to align incentives to promote high-quality care, but results have been contradictory. OBJECTIVE: To test the effect of explicit financial incentives to reward guideline-recommended hypertension care. DESIGN, SETTING, AND PARTICIPANTS: Cluster randomized trial of 12 Veterans Affairs outpatient clinics with 5 performance periods and a 12-month washout that enrolled 83 primary care physicians and 42 nonphysician personnel (eg, nurses, pharmacists). INTERVENTIONS: Physician-level (individual) incentives, practice-level incentives, both, or none. Intervention participants received up to 5 payments every 4 months; all participants could access feedback reports. MAIN OUTCOMES AND MEASURES: Among a random sample, number of patients achieving guideline-recommended blood pressure thresholds or receiving an appropriate response to uncontrolled blood pressure, number of patients prescribed guideline-recommended medications, and number who developed hypotension. RESULTS: Mean (SD) total payments over the study were $4270 ($459), $2672 ($153), and $1648 ($248) for the combined, individual, and practice-level interventions, respectively. Change in blood pressure control or appropriate response to uncontrolled blood pressure compared with the control group was significantly greater only in the individual incentives group. Change in guideline-recommended medication use was not significant compared with the control group. The effect of the incentive was not sustained after a washout. CONCLUSIONS AND RELEVANCE: Individual financial incentives, but not practice-level or combined incentives, resulted in greater blood pressure control or appropriate response to uncontrolled blood pressure; none of the incentives resulted in greater use of guideline-recommended medications or increased incidence of hypotension compared with controls. Further research is needed on the factors that contributed to these findings. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00302718.