Washingtonians complain they've been caught off guard by exorbitant medical bills despite having health insurance.

The sticker shock comes from a practice known as balance billing.

Balance billing happens when medical providers such as doctors and insurance companies fail to negotiate a deal and medical providers send the patient the remaining part of the bill the insurance company won't cover.

When that happens the medical provider sending the bill is considered "out of network" by the insurance company.

For now, balance billing is perfectly legal in Washington state but there's an effort under way to pass new legislation protecting consumers from this type of medical bill.

Karen Sticklin received a balance bill for a series of biopsy tests to confirm she did not have breast cancer after an unusual mammogram.

"I think what added insult to injury was that it was for a breast biopsy and I'm already anxious about it," Sticklin said. "Then, I have to get this bill for almost $600. It's unjust and I don't intend to pay it."

It all started when Sticklin went to Swedish Medical Center for her yearly mammogram and doctors told her she would need a biopsy.

"I was stressed out of course," Sticklin said.

Sticklin remembered to confirm both the hospital and doctor providing her care were accepted her insurance, Premera.

Then without any warning, Sticklin says Swedish sent her biopsy to an out of network lab called Cellnetix.

That lab billed Karen the balance the insurance company wasn't willing to pay.

KING 5 later obtained a letter Premera sent to Swedish asking providers at the facility to send patients' lab work somewhere other than Cellnetix but Swedish did not comply.

In a statement, Swedish Communications Manager Karrie Spitzer told KING 5, "Temporarily switching labs for specific tests during insurance disputes is not necessarily in our patients' best interests. In this case, we work with Cellnetix for pathology tests because we know that they consistently provide accurate and reliable test results which are needed for diagnosis and treatment."

Spitzer added that Swedish asked Premera to treat its patients lab work at Cellnetix as in-network even though it was technically out-of-network during the dispute.

"Consumers cannot be treated this way," Washington state Insurance Commissioner Mike Kreidler said.

Kreidler proposed a bill to end balance billing this past legislative session. He had hoped lawmakers would pass HB2447 which would have required insurance companies and providers to resolve disputes about out of network fees through arbitration.

"The consumer is playing by the rules. They shouldn't be penalized," Kreidler said.

Kreidler's proposal failed after facing opposition from doctors, hospitals and insurance companies.

"That is an onerous administrative burden and would increase the cost of healthcare for everyone," said Senior VP of Healthcare Delivery Systems for Premera Beth Johnson.

"Why do we want to make systems that just cost the consumers money?" asked Assistant Secretary-Treasurer for the Washington State Medical Association Dr. Nathan Schlicher.

Both medical providers and insurance companies worried that the costs related to arbitrating bill disagreements would be high and ultimately passed down to consumers in the form of higher prices for healthcare.

However, it's not just consumers doctors and insurance companies are worried about.

At its core this issue is largely a dispute about prices between the two entities.

"If I'm legally required to take care of you, what incentive does the other side have, AKA the insurance company, have to negotiate?" Schlicher said.

On the other side are insurance companies. Johnson is involved in those negotiations for Premera.

"We need to make sure we are keeping healthcare affordable. So, we do our best to stay within a range for reimbursement," Johnson said.

Representative Eileen Cody chairs the State House and Wellness Committee. She's also leading negotiations already underway for a second attempt at new legislation.

"We need to take the patient out of the equation," Cody said.

Cody says balance billing shouldn't be legal in the case of emergency care and in situations like Karen's when the patient isn't warned that a provider is out of network.

Cody said she is determined to reach a compromise all sides of the issue can live with.

Sticklin isn't shy about what she thinks the solution should be. After all, she does have a "Bernie" sign in her front yard in support of Senator Bernie Sanders' bid for the Democratic nomination.

"I think the one-payer healthcare, that if we had a decent health care system like other countries, most other industrialized nations, we wouldn't have to stress about it," Sticklin said.

KING 5 reached out to Sticklin's insurance, the medical center she visited and the lab who processed her tests.

KING 5 also connected Sticklin directly to Rep. Cody.

Not long after, KING 5 received an email that Cellnetix and Premera had reached an agreement and Sticklin no longer owed anything.

Both companies also reiterated their commitment to patient.

"We want to keep them out of that situation and we do our best to do that," Johnson said.

Sticklin was relieved.

"Will be nice to have an extra $600 in my pocket. Not sure what I will do with it," Sticklin said.

Negotiations are already underway in Olympia in the hopes of drafting a new piece of legislation to protect consumers behind balance billing that also has the support of industry insiders ahead of next year.

Both the Medical Association and Premera, one of the largest insurers in Washington, have said they are open to the idea of arbitration but only in very select circumstances.

If you have received a surprising medical bill, we want to hear from you.

Go to King5.com/shareyourbills and use the online form to tell us your story or you can email us directly at shareyourbills@king5.com.