Starting Saturday, private insurers must cover the cost of up to eight at-home Covid-19 tests per month, the Biden administration announced on Tuesday.

"We are requiring insurers and group health plans to make tests free for millions of Americans. This is all part of our overall strategy to ramp-up access to easy-to-use, at-home tests at no cost," said U.S. Department of Health and Human Services (HHS) Secretary Xavier Becerra, in a statement.

Covid tests purchased after Jan. 15 will be covered by almost all private insurers, but there are other ways you can currently get free tests, too.

What you need to know

You're now entitled to up to eight over-the-counter at-home tests per month, which must be fully reimbursed by your insurance company, with no deductibles or cost-sharing. Packages that include multiple tests will be considered a single test for the purpose of reimbursement.

Additionally, test kit costs are covered if they're part of a clinical assessment by a health-care provider. That means you get eight free tests month, plus whatever number of tests a doctor asks you to take.

The tests must also be approved by the Food and Drug Administration. To know if a test is eligible, check here for a searchable list of approved rapid antigen-based tests and here for molecular-based (PCR) tests. 

Pretty much every type of private health insurance is covered, including employment-based group health plans, state-run plans and church plans. Limited-term plans are excepted, as are plans that only cover specific health-care treatments, like dental care.

Aside from private insurers, state Medicaid and Children's Health Insurance Program (CHIP) programs are currently required to cover FDA-authorized at-home tests without cost-sharing, according to HHS. At this time, Medicare can't pay for at-home tests through this program, although the tests are free if ordered by a health-care professional. 

If you don't have health insurance, you can get a test for free at U.S. Department of Health & Human Services (HHS) health centers, or possibly at other testing centers run by your local states or municipality, as well as schools. For more information on your options, check out this CNBC Make It story.

The Biden administration also recently announced that 500 million at-home kits would be sent to people who need them, through a website slated to launch in January. In a Monday press briefing, Press Secretary Jen Psaki said that more details about the website, as well as a hotline, are expected to be provided this week.

How to get your at-home Covid test kits reimbursed

As of Saturday, you should be able to purchase a kit from a pharmacy, store or online retailer and make a claim with your insurer using the receipt from your purchase.

The Biden administration says that there are plans to incentivize insurers so that the reimbursement process is automatic at the point of purchase, without having to file a claim, but that's still in the works.

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