GGT Blood Test Cost and Medicare Coverage (CPT 82977)

Also called: gamma-glutamyl transferase · gamma GT · GGTP · gamma-glutamyl transpeptidase — all the same test, CPT 82977.

National policy — the same Medicare rules apply in every state what's this?

This test is governed by a National Coverage Determination (NCD) — a rule issued by CMS, the federal agency that runs Medicare. It spells out which diagnoses justify the test and any frequency limits, it applies identically in all 50 states, and no regional contractor can override it. What you read on this page is the rule everywhere.

Does Medicare cover it?: Only for certain diagnoses — such as known or suspected liver or bile-duct disease, a medication that can harm the liver, alcohol use, hepatitis, diabetes and other conditions known to affect the liver (examples only; details below)
You pay if covered: $0 — no deductible, no coinsurance
Medicare pays the lab: $7.20
Information verified: 2026-09-27

Buy it yourself — what you'd really pay

Where	Test price	Fee	Total
Jason Health jasonhealth.com	$5	$18 one fee per order — covers every test on it	$23
Ulta Lab Tests ultalabtests.com Partner link — we earn a commission if you order. No extra cost to you.	$23.95	$12.95 draw fee — one per order, covers every test on it	$36.90
Personalabs personalabs.com · price includes the draw; not a partner — we earn nothing from this row	$49	—	$49
Labcorp ondemand.labcorp.com	$59	—	$59
Quest questhealth.com · not sold alone — only inside a liver function panel (ALT, AST, ALP, bilirubin, albumin, platelets, and more)	$119	$6 physician service fee	$125

Disclosure: the Ulta Lab Tests link above is a partner link. If you order through it, ClaraCover earns a commission. It costs you nothing extra, and it never changes what we tell you about Medicare coverage.

The short answer

Covered when your doctor is looking at your liver or bile ducts for a reason. Medicare’s national policy (NCD 190.32, the same in every state) covers GGT for known or suspected liver or bile-duct disease, for people taking medications that can harm the liver, after alcohol or drug use, after hepatitis or similar infections, for cancers, and for conditions that are known to affect the liver, such as diabetes. It also covers GGT to sort out whether a high alkaline phosphatase (ALP) is coming from the liver or from bone.

What is not covered is GGT added to routine bloodwork with nothing liver-related on the order. GGT is not part of the comprehensive metabolic panel, so it is billed on its own, and on its own it needs its own reason.

When Medicare DOES cover it

The national policy lists seven situations. In plain English:

Known or suspected liver or bile-duct disease, including after long-term alcohol or drug use, after exposure to something toxic to the liver, while taking a medication known to cause liver toxicity (checked on the schedule the drug’s maker recommends), or after an infection such as viral hepatitis
Cancer, to check whether the liver is affected by a primary or secondary tumor
Conditions known to involve the liver, with the policy’s own examples being diabetes, malnutrition, disorders of iron and mineral metabolism, sarcoidosis, amyloidosis, and lupus
Digestive (gastrointestinal) disease, to assess liver function
Pancreatic disease, to assess liver function
After a liver transplant
A high alkaline phosphatase (ALP) result, to tell whether the ALP is coming from the liver or from bone

The diagnosis code list behind this policy is long, about 3,900 codes: it includes alcoholic and non-alcoholic liver disease, cirrhosis, hepatitis B and C, gallstones and bile-duct problems, jaundice, an “elevated liver enzymes” finding, alcohol use disorder, long-term use of many medications, diabetes, and high cholesterol. If one of these genuinely describes your situation, the diagnosis for it belongs on your doctor’s order, and coverage follows.

When Medicare does NOT cover it

Routine screening, with no liver-related reason on the order. Fatigue, a wellness visit, high blood pressure on its own, anemia, and vitamin D deficiency are not on the covered list.
Repeating a normal result when the reason was a non-liver condition and nothing has changed. The policy says a repeat after a normal GGT is generally not necessary unless something new comes up.
More than once a week when the test is being used to sort out a high ALP.
Routine monitoring of known liver disease. The policy says GGT is so sensitive that it is generally not useful for tracking a liver condition that has already been diagnosed; other tests do that job.

(Never ask anyone to change a code just to get coverage; that is fraud. But doctors often have a legitimate reason for the test that simply wasn’t written down.)

What you pay if it IS covered: $0

Covered lab tests cost Medicare patients nothing, with no deductible and no 20% coinsurance. Medicare pays the lab $7.20 for a GGT test, and you owe zero.

What you pay if it is NOT covered, read this before you sign

Quest’s own test directory flags GGT as “subject to a Medicare Limited Coverage Policy” that “may require a signed ABN when ordering.” If GGT is on your order without a qualifying diagnosis, expect the Advance Beneficiary Notice (ABN), the signature pad, committing you to the lab’s own billing rates if Medicare denies the claim. Before you sign:

Ask the lab to print exactly what you would owe. You’re entitled to see the number in black and white first. For perspective: when Medicare covers this exact test, it pays the lab $7.20.
Know the direct prices: GGT sells for $5 at Jason Health (jasonhealth.com, plus their flat $18 lab-collection fee per order, one fee for the whole order) and $59 at Labcorp OnDemand; Quest’s consumer site sells it only inside a $119 liver function panel (plus a $6 physician fee). The full table is above. Same certified labs, same blood draw. GGT is one of the cheapest tests a lab runs, so a large ABN figure for it deserves a question.

Before you sign the pad, 60-second checklist

Ask: “Can you print what I’ll owe if Medicare doesn’t pay?”
Ask your doctor: “Is there a liver-related reason for this test, like a medication I take or an earlier abnormal result?”
Compare the printed price to the direct-purchase prices before deciding how to proceed.

What counts as a “normal” GGT level

Start with the range printed on your own report. Published ranges for GGT exist, but they differ, and every source says the same thing: compare your result to your own lab’s range.

The MedlinePlus Medical Encyclopedia gives an adult range of 5 to 40 U/L, and adds that normal ranges “may vary slightly among different laboratories.”
Cleveland Clinic says the normal range “is often below 50 U/L, but it can vary based on the lab that performs the test,” and that GGT runs somewhat higher in men and changes with age.
Labcorp’s own reference interval is 0 to 65 IU/L for men and 0 to 60 IU/L for women.

None of the sources we checked gives a treatment target for GGT the way the ADA does for A1c, so there is no “clinical target” to add here. Alcohol, smoking, and a number of common medications raise GGT, which is one reason a single high result is a question for your doctor rather than a diagnosis.

(Where lab ranges and “optimal” ranges come from, and who decides.)

This page can tell you where those numbers came from. It cannot tell you what yours means; that reading belongs to your doctor, alongside your history and your other results.

Quick questions people ask

What is a GGT blood test? GGT (gamma-glutamyl transferase) is an enzyme found mainly in the liver. The test measures how much of it is in your blood. Higher-than-normal levels can be a sign of liver damage or a blocked bile duct, from causes as different as hepatitis, fatty liver, alcohol, and medication side effects; the result shows that the liver is irritated, not why. On billing paperwork it is CPT code 82977.

Why is GGT ordered with alkaline phosphatase (ALP)? Both go up with liver and bile-duct problems, but ALP also goes up with bone conditions and GGT does not. High ALP with high GGT points to the liver; high ALP with a normal GGT points away from it. That is the exact situation Medicare’s policy names as a covered use.

Is GGT part of the comprehensive metabolic panel? No. The comprehensive metabolic panel includes ALT, AST, ALP, and bilirubin, but GGT has its own code and is billed separately, which is why it can be denied on its own even when the panel is covered.

Do you have to fast for a GGT test? Ask. MedlinePlus notes that GGT levels go down after meals and your provider may ask you to fast; Labcorp asks for an 8-hour fast; Quest’s directory lists no preparation. Cleveland Clinic says not to drink alcohol for at least 24 hours before the test, because even small amounts raise GGT. If your order doesn’t say, call before the day. Our fasting guide explains what fasting means and what you can still drink.

How long does a GGT test take? The blood draw takes minutes, and results are typically back in one to three business days, direct-purchase orders included.

Sources and data dates

Medicare payment amount: CMS Clinical Laboratory Fee Schedule, 2026 Q3 file (national rate). Coverage rules: CMS Medicare Coverage Database, NCD 190.32 (Gamma Glutamyl Transferase), a national policy identical in every state, and the same text in the NCD Manual, Chapter 1, Part 3. Test descriptions and preparation: MedlinePlus (lab-tests page and Medical Encyclopedia), Cleveland Clinic, Labcorp test 001958, Quest test 482. Consumer prices checked September 2026. Information current as of the date shown above; coverage is always determined by Medicare when your claim is processed.

ClaraCover provides information, not medical, billing, or insurance advice. Talk to your doctor about what tests you need.

Covered diagnoses for CPT 82977

Medicare's national rule for this test, NCD 190.32, Gamma Glutamyl Transferase, comes with a list of 3,937 ICD-10 diagnosis codes that support it (CMS's laboratory code list, updated every quarter). In plain English, the covered situations are the ones described on this page: known or suspected liver or bile-duct disease; a medication that can harm the liver; alcohol use; hepatitis; diabetes and other conditions known to affect the liver. A claim whose diagnosis is on the list pays; a claim without one is denied as not medically necessary unless another provision of the rule applies.

Billing office? The full list, a batch check, and no daily limit are what we are building for you: tell us you want it. For why lab tests are the one place Medicare gives a straight answer, see what "reasonable and necessary" means.