CHICAGO — At-home COVID-19 rapid tests will soon be free to many people, following an announcement Monday that President Joe Biden’s administration will require insurance companies to cover their cost.

But despite that requirement being slated to take effect Saturday, some details of how it will work remain nearly as scarce as the tests themselves, which have been in short supply in recent weeks.

Here’s what we do (and don’t) know so far:

Q: Who will be able to get the tests for free?

A: The Biden administration is requiring insurance companies and group health plans (such as those typically offered by employers) to cover the costs of tests for members. People who buy their own insurance plans will also be eligible for the free tests.

State Medicaid and Children’s Health Insurance Program, or CHIP, programs, which are for lower-income individuals and families, are already required to cover the tests.

Traditional Medicare will not cover the costs of over-the-counter, at-home tests through this new program, though people on Medicare may be able to get free at-home tests through community health centers and Medicare-certified health clinics and through a new, federal website expected to be unveiled later this month.

People with Medicare Advantage plans should check with their individual plans to see if they’re covering over-the-counter, at-home tests.

Q: What types of tests will be covered? How many?

A: The new requirement will apply to over-the-counter COVID-19 tests that have been authorized, cleared or approved by the U.S. Food and Drug Administration. That includes a number of tests, such as the popular BinaxNOW test made by Abbott Laboratories.

The tests generally involve swabbing the nose at home and then waiting 10 to 15 minutes for results.

Q: How many tests can a person get for free?

A: Insurance companies will be required to cover eight over-the-counter, at-home tests each month, per person on a plan. That means if there are four people in a family, all covered by the same insurance plan, the family could get 32 free tests a month.

Q: Will there be any upfront cost to buy tests?

A: This is where things get tricky. The administration is requiring insurers to cover the costs of the tests in one of two ways. Insurers can pay for them upfront, meaning a consumer could go into a pharmacy, pick out a test, show an insurance card and then walk out with a test without paying any money.

Or, insurers can have a consumer pay for a test at the pharmacy and then seek reimbursement by submitting a claim to the insurer.

Neither of Illinois’ two largest health insurance companies, Blue Cross and Blue Shield of Illinois or UnitedHealthcare, answered questions Tuesday about which methods they plan to use.

Blue Cross spokeswoman Colleen Miller said in a statement, “We are analyzing the Biden-Harris Administration’s mandate to cover (over-the-counter) home Covid-19 tests and we will be prepared to implement according to the government’s guidelines.”

A spokesperson for Walgreens said the retail pharmacy chain was “awaiting further guidance from federal and regulatory agencies on reimbursement.”

Spokespeople for Walmart and CVS Health did not respond by deadline Tuesday to requests for comment on details of how consumers would be able to get the tests for free at their stores.

People will be able to buy the tests at stores and through online retailers.

Q: How do I get reimbursed for tests?

A: Starting Saturday, if you have to pay upfront for an over-the-counter, at-home COVID-19 test, keep your receipt. Contact your insurance company for more information about how to submit a claim.

How much you’ll be reimbursed depends on how your insurance company handles this new requirement.

The Biden administration is trying to incentivize insurers to make the tests available with no upfront costs by asking them to set up networks of preferred pharmacies, stores or online retailers where people can get the tests without handing over cash. Insurance companies that do that will only have to reimburse people up to $12 a test if they buy the tests at stores or retailers outside of those networks.

Insurance companies that don’t set up those networks will be required to reimburse people the full costs of the tests, even if they exceed $12.

Q: Can uninsured people get the rapid, at-home tests for free?

A: Not through this new requirement, but the Biden administration plans to distribute 500 million over-the-counter, at-home tests starting later this month. People, regardless of their insurance status, will be able to order those through a website that has not yet been made public.

Uninsured people can also get free, at-home tests from some community health centers, and Medicare-certified health clinics.

Q: Can I get reimbursed for tests I bought before Saturday?

A: You can try, but insurance companies are not required to cover those.