In January, the Affordable Care Act (ACA) will require all Americans to purchase health insurance or pay a penalty. How will this law affect you and your family?

Nancy Metcalf, health insurance editor for Consumer Reports, says it won’t be a big change for many. “A majority of Americans under the age of 65 obtain their health insurance through a job,” she says, “and that will continue to be the case.”

As part of the new law, online health insurance “marketplaces” can help consumers compare and purchase insurance plans. Open enrollment begins Oct. 1. Middle-and lower-income families can receive subsidies to help pay for insurance and may qualify for expanded Medicaid coverage in some states.

The penalty for not having insurance will rise annually until reaching its cap of 2.5 percent of household income in 2016 and beyond. Though the penalty may cost less than some plans, Metcalf cautions “it is never beneficial not to have insurance.”

Also under the ACA, children younger than age 26 are allowed to be covered on their parents’ insurance even if they are married, in school or eligible for employer coverage.

The ACA also protects people with pre-existing medical conditions. “The law requires health insurance companies to provide coverage and not discriminate, and not to charge more to individuals based on whether or not they’ve had a pre-existing health condition,” says Andrew Hyman, senior program officer at the Robert Wood Johnson Foundation, the nation’s largest philanthropic organization devoted solely to health and health care.

To learn more about how the Affordable Care Act will affect your family’s healthcare coverage options, visit healthcare.gov.