HHS: Health law gave millions free preventive care

One such benefit is the law's Annual Wellness Visit for Medicare beneficiaries with a doctor of their choice.

The exam reviews patients' health and introduces "education and counseling about preventive services and other care," according to Healthcare.gov. HHS stated that 1.35 million seniors have used their visit this year so far.

Other free preventive services include shots for pneumonia, hepatitis B and the flu, HIV screenings and help quitting smoking.

A total of 32.5 million people in Medicare received one free preventive benefit or more last year, according to HHS. These seniors would have paid for some of the value of the service before the healthcare law was enacted.