Hospitals bill everyone the same, from Medicare to private insurers to the uninsured. But the full tab that appears on your bill is much higher than the hospital's actual costs. That's called the hospital's charges-to-cost, or markup, ratio, and nationally the average is about three to one, says Gerard Anderson, director of the Johns Hopkins Center for Hospital Finance and Management.

Medicare traditionally compensates hospitals based on their actual costs, and private insurers that bring in many patients also have the clout to negotiate rates that are closer to a hospital's actual costs. Only patients who are uninsured or underinsured are expected to pay the fully loaded sticker price.

But that doesn't mean you have no wiggle room. Start by asking how much Medicare would pay for a procedure similar to yours. Armed with that information, Anderson says, go straight to the hospital's chief financial officer and ask the hospital to send you a revised bill that reflects the actual cost plus 25 percent.

Bolster your case by showing you're serious about paying. A good way to do that is to offer to pay immediately once you secure a sizable reduction in charges.

In 2004, Kristine Arnould landed in Mercer Medical Center, in Trenton, N.J., with a pulmonary embolism. After X-rays, an MRI scan and five days on a drug drip, Arnould was presented with a bill for $37,000. The self-employed real estate agent was uninsured at the time but earned too much to qualify for charity care.

Arnould tried to negotiate the bill but was met with a brick wall of resistance. "I called them up and said I was willing to pay fair market value or what Medicare or an insurance company would pay," she says. "But they said, 'Nope, that's your bill."' She began sending the hospital monthly checks for $25, along with letters contesting her bill, which was eventually turned over to a collection agency.

Arnould caught a break when Web research led her to the Chapman Consulting Group (, an Austin, Texas, firm that helps patients determine how much they reasonably ought to pay. For a $75 fee, Chapman reviewed Arnould's situation and advised her to negotiate a bill of no more than $7,500.

A tip from a friend led Arnould to the Access Project, where she spoke with Andrew Cohen, who coached her on how to phrase her request to the hospital. This time, her negotiating worked. Arnould had already paid $3,000 on her bill over the previous two years, and the hospital agreed to settle for another $3,000, provided she paid the remainder within 60 days.

Elizabeth Ody is a staff writer at Kiplinger's Personal Finance magazine. Send your questions and comments to [email protected].