COVID-19 testing is supposed to be free, but some people have received bills for hundreds or even thousands of dollars.

This doesn't happen often - one study found patients only get billed for COVID tests about 2% of the time. But when it does happen, it can be costly. 

Kelly Daisley saw an ad for free testing back in June and got tested at a clinic near her Brooklyn home. She then received a denied claim for more than $1,800 for the test and more than $200 for an antibody test. Her insurance wasn't going to cover any of it.

 "Called my insurance company and the man I spoke with says, he says, 'Well, it's an out-of-network lab.' I said, 'I don't care if it's in network or out. The ads say it's free,'" says Daisley.

Under the CARES Act, COVID-19 testing is supposed to be free and without copays or deductibles. Insurers are even supposed to pay for out-of-network care. Health care advocate AnnMarie McIlwain says the system doesn't always work, however.

 "We are seeing examples around the country where some of those providers are, shall we say submitting bills that make no sense, that are incredibly high," says McIlwain. 

McIlwain says oftentimes the bill was just coded wrong.

You can protect yourself by confirming up front if the test will be covered. Check if there are free testing sites nearby. If you get a bill for a COVID test, appeal with your insurance company. 

Daisley's insurance company ultimately acted to pay the bill, but she is wary about future testing and potentially risking another fight.