Objective To determine the effectiveness and safety of erenumab in patients with chronic migraine in the real‐world setting of 3 headache centers in Australia. Methods Patients with migraine were prescribed erenumab (70 or 140 mg) in the setting of either a product familiarization program or paid access to the medication in 3 headache centers in Australia. We obtained baseline and monthly prospective data on monthly headache days, monthly migraine days, monthly triptan use days, monthly codeine use days, Headache Impact Test‐6 scores, and adverse reactions. In this paper, we present our data at 3 and 6 months in our subgroup of patients with chronic migraine with and without medication overuse. Results A total of 170 patients with chronic migraine were prescribed erenumab in the 3 headache centers. At 3 months, 100/170 (58.8%) had 50% or greater reduction in monthly migraine days. At 6 months, 79/170 (46.5%) had 50% or greater reduction in monthly migraine days. At 6 months, there was a mean reduction in monthly headache days of 9.2 days, a mean reduction in monthly migraine days of 10.2 days. There were few adverse events reported. Conclusion This is the first report from 3 Australian headache centers about erenumab in the real world. Our analysis has supported erenumab as an effective and well‐tolerated migraine preventative therapy for patients with chronic migraine who have failed many preventative therapies.