Background: An arteriovenous fistula (AVF) is the recommended vascular access for hemodialysis (HD). Previous studies have not examined the resources and costs associated with creating and maintaining AVFs. Study Design: Retrospective observational study. Setting & Participants: Elderly US Medicare patients initiating hemodialysis therapy during 2010 to 2011. Predictor: AVF primary and secondary patency and nonuse in the first year following AVF creation. Outcomes: Annualized vascular access costs per patient per year. Results: Among patients with only a catheter at HD therapy initiation, only 54% of AVFs were successfully used for HD, 10% were used but experienced secondary patency loss within 1 year of creation, and 83% experienced primary patency loss within 1 year of creation. Mean vascular access costs per patient per year in the 2.5 years after AVF creation were $7,871 for AVFs that maintained primary patency in year 1, $13,282 for AVFs that experienced primary patency loss in year 1, $17,808 for AVFs that experienced secondary patency loss in year 1, and $31,630 for AVFs that were not used. Similar patterns were seen among patients with a mature AVF at HD therapy initiation and patients with a catheter and maturing AVF at HD therapy initiation. Overall, in 2013, fee-for-service Medicare paid $2.8 billion for dialysis vascular access–related services, ∼12% of all end-stage renal disease payments. Limitations: Lack of granularity with certain billing codes. Conclusions: AVF failure in the first year after creation is common and results in substantially higher health care costs. Compared with patients whose AVFs maintained primary patency, vascular access costs were 2 to 3 times higher for patients whose AVFs experienced primary or secondary patency loss and 4 times higher for patients who never used their AVFs. There is a need to improve AVF outcomes and reduce costs after AVF creation.