If there's a mistake, it could be as simple as a routine checkup being improperly coded as an urgent-care visit. Or, you could be given the generic form of a medicine and yet charged for the brand name, or you might get charged twice for the same service.
Additionally, always make sure you receive an itemized explanation of what you owe instead of a bottom-line amount, Lipezker said. Also, be sure to check your bills against the explanation of benefits sent by your insurance company.
Errors tend to be more prevalent when you end up in the hospital. Due to the variety of doctors who tend to you and tests or procedures ordered, there can be many different individual providers that end up filing a claim with your insurance company.
The result can be a confusing mess of explanatory paperwork from your insurance company, along with bills from multiple doctors or other providers. Hang on to everything, and don't be shy about seeking help if you need it.
More from Personal Finance:
At this company, you can trade a vacation for student loan relief
Most of the 55-and-older crowd do little planning for end of life
9 vacation spots you can actually afford for 2019
The first place to turn is your company. Many firms include advocacy services as a benefit for employees who need help making sense of bills or checking for errors and getting them fixed. If your employer has this perk, take advantage of it. If you're unsure, ask your human resources department.
There also are specialized advocacy firms you can turn to. They typically review bills for free and take a cut of whatever amount they saved you.
The bottom line is to make sure the amount you're being asked to pay is accurate, Lipezker said.
"You might be pleasantly surprised to find that it's correct," she said. "But many times it's not.
"And the more you dig in and care about what's on that bill, the more you'll be able to understand the next time."
Subscribe to CNBC on YouTube.