How to Dispute a Lab Bill: What to Check and What Rights You Have

Laboratory bills are among the most error-prone medical bills patients receive. The separation between the facility that collected your specimen, the laboratory that analyzed it, and the physician who ordered the test creates multiple billing touchpoints where errors occur.

Why lab bills are especially confusing

You may receive multiple bills from a single lab encounter. The facility that drew your blood bills separately from the laboratory that analyzed it. The physician who ordered the test bills their office visit separately. An outside reference laboratory that received an overflow specimen may bill independently.

Each of these bills goes through a separate claims process. Each can be processed differently by your insurer depending on network status and benefit design.

What to check on your lab bill

Confirm that every test billed was actually ordered by your physician. Compare the tests on your bill against the test orders or the lab results you received. Tests ordered but cancelled before analysis should not be billed.

Check whether the laboratory is in-network. Hospital-based laboratories are often in-network when the hospital is, but independent reference laboratories contracted by your physician's office may not be. If the lab was out-of-network, you have different rights depending on whether you had a meaningful choice in selecting it.

Verify that the diagnosis codes on the lab claim match your condition. An incorrect diagnosis code can cause a denial even for tests that are medically appropriate for your actual condition.

Reference laboratory billing and the No Surprises Act

When your in-network laboratory sends your specimen to an out-of-network reference laboratory, the No Surprises Act may apply. If you did not knowingly choose the reference laboratory and had no opportunity to select an in-network alternative, balance billing protections may limit your exposure.

How to dispute

Request an itemized statement from the laboratory showing each test with its CPT code, the quantity, and the price. Compare this against your physician's orders and your EOB.

For tests not ordered by your physician, contact the laboratory billing department in writing with documentation. For network disputes, contact your insurer to verify whether the laboratory was in-network and whether the No Surprises Act applies.

For diagnostic codes causing incorrect processing, ask your physician's office to verify the codes submitted and request a corrected claim if there is an error.

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Bill Advantage is a document literacy tool. Nothing in this article constitutes legal or medical advice.