Read -- and save -- your mail. It's not a bad idea to start a folder where you can save all the correspondence and bills you receive about the accident. You can also use it to store handwritten notes you take if you talk with anyone over the phone about the accident.

When you receive a bill, don't just assume that the insurance company will take care of it. "That's where people get in trouble," warns attorney Robertson. "They let it go because they think insurance is going to take care of it, and next thing they know, it is in collections." 

Contact the medical provider if you aren't sure it has all your up-to-date insurance information. "Double-check all the information they have on file is correct. The most common denial that providers see is for member ID mismatches," Vahle says.

Also read the explanation of benefits statements that you receive from insurance companies. If an EOB lists a balance as "patient responsibility," contact the medical provider to find out whether other insurance will be billed for that amount, or if you need to pay it yourself.

Beware balance billing. If your health care provider is in-network, then there's a good chance that it is required to follow certain billing procedures. If the provider fails to bill in a timely manner, for example, it may not be allowed to bill the patient for that claim. "Or it may not be allowed to try to collect the difference between the billed amount and the amount the insurance company agrees to pay," explains Vahle. Talk with your insurance company it you think a provider is trying to balance-bill you.

Ask your insurance agent for help, suggests Greg Isaacs, the president of CoverHound Insurance Solutions, an online insurance comparison website. Even if the insurer you're having trouble with is not your own, your independent agent may have relationships with other insurance companies that can help. "Plus (your agent) speaks the language," he adds.

Be a squeaky wheel. Isaacs warns that most claims adjusters are overworked, and sometimes the most persistent customers get their claims processed first. While you want to remain polite and calm, letting them know you are staying on top of your claim can help. If an insurance company is taking forever to process a claim, then "don't be afraid to escalate things," says Isaacs. "In most states, you can file a complaint with the state regulator about how a claim has been handled," he notes. "They have to respond to those claims."

Hire a personal injury attorney. "One of the key jobs an attorney has is to try to help keep the bills out of collections," says Robertson. "That's what we do every day." Your attorney should be familiar with most medical billing procedures in the case of accidents and may be able to ask a provider to hold off on collection until a settlement is reached. It's best to talk with an attorney as soon as possible after the accident, so you can avoid problems that may develop. But it you haven't, you can consult one later in the process as well. Most personal injury attorneys offer a free consultation and work on a contingent-fee basis, which means there is no payment unless there is a recovery.

Challenge a denial. Don't assume that a denial by an insurance company is the final word. "If insurance coverage has been denied or the decision by an insurance company has been delayed, an attorney may be able to help," says attorney Deming. "In fact, I am currently preparing for trial for a medical bill which was denied under personal injury protection coverage."

Negotiate. If it turns out you are responsible for some of the medical bills that result from an accident, you may be able to negotiate a reduction in the amount you owe. If you are working with an attorney, "the attorney may be able to negotiate that with the medical provider" on your behalf, says Deming.

If you are not working with an attorney, and you are overwhelmed with the process of understanding or challenging your medical bills, you may want to turn to a patient advocate -- an expert who helps patients analyze, dispute and even negotiate medical bills. The website Copatient, for example, offers a free review of medical bills with additional services billed as a percentage of the money saved by the client. Alternatively, current or retired labor union members may be able to tap into a free medical bill negotiation service.

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