The Affordable Care Act requires health insurers to justify rate increases that are 10 percent or more for nongrandfathered plans in the individual and small-group markets. Analyzing these filings for renewals taking effect from mid-2013 through mid-2014, this brief finds that the average rate increase submitted for review was 13 percent. Insurers attributed the great bulk of these larger rate increases to routine factors such as trends in medical costs. Most insurers did not attribute any portion of these medical cost trends to factors related to the Affordable Care Act. The ACA-related factors mentioned most often were nonmedical: the new federal taxes on insurers, and the fee for the transitional reinsurance program. On average, insurers that quantified any ACA impact attributed about a third to these new ACA assessments.