Iron Panel Cost and Medicare Coverage (CPT 83540, 83550)

Also called: serum iron and TIBC · iron studies · iron saturation · transferrin saturation · Fe and TIBC — all the same test, CPT 83540 (related codes: 83550, 84466).

The short answer

Covered when your doctor is working up or managing an iron problem, and only in the combination the policy expects. Medicare’s national policy (NCD 190.18, the same in every state) covers serum iron, TIBC, and transferrin for diagnosing iron deficiency, anemia, and iron overload, for monitoring treatment, and for checking toxic exposure to iron and other metals.

Two rules in that policy are the reason iron studies get denied even when there is a real reason for them. The policy says it is not ordinarily necessary to run both iron/TIBC and ferritin on the first round of testing, and not ordinarily necessary to run both TIBC and transferrin at all, because TIBC is just an indirect way of measuring transferrin. A lab order that carries all four codes “to check your iron” is asking Medicare to pay for tests its own policy calls redundant.

This page covers the three panel codes. The ferritin test, the fourth iron study, has its own page under the same policy.

What the three tests are

• Serum iron (CPT 83540) measures the iron circulating in your blood at that moment. It swings with meals and with the time of day.
• TIBC (CPT 83550) measures how much iron your blood could carry. It rises when iron is low and falls with inflammation, liver disease, or malnutrition. Labs report transferrin saturation (iron divided by TIBC) alongside it, and most consumer “iron panels” are exactly these two codes plus that calculation.
• Transferrin (CPT 84466) directly measures the protein that carries iron. It answers the same question as TIBC, which is why the policy says you do not need both.

When Medicare DOES cover it

The national policy’s covered picture, in plain English:

• Working up suspected iron deficiency: an abnormal blood count (small red cells, low hemoglobin, or a wide red-cell size spread), pica, blood loss from the stomach or bowel, blood in the urine, heavy menstrual bleeding, malabsorption, stomach surgery, malnutrition, banking your own blood before surgery, anemia alongside cancer or chronic inflammatory or infectious conditions, or blood loss from a major operation that was not replaced with iron
• Working up suspected iron overload: the hemochromatosis picture, with the policy’s own examples being chronic hepatitis, diabetes, darkening skin, joint disease, cirrhosis, low sex hormones or pituitary function, porphyria, heart failure, multiple transfusions, sideroblastic anemia, thalassemia major, and heart rhythm or muscle problems
• Monitoring treatment: oral or intravenous iron, vitamin C, or erythropoietin
• After treating B12 or folate deficiency, because fixing one deficiency can unmask an iron problem
• Toxic exposure: serum iron is also covered to evaluate the toxic effects of iron and other metals, the policy names nickel, cadmium, aluminum, and lead, whether from an accident, an intentional exposure, or a metabolic cause

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

• “Check my iron” with nothing behind it. The policy says iron studies are for diagnosing and managing iron deficiency or overload, and are not for tracking inflammation when the result would not change your care.
• Both TIBC and transferrin together. The policy says it is ordinarily not necessary to measure both at the same time.
• Iron/TIBC and ferritin together on the first round. The policy says that is not ordinarily necessary either; once a diagnosis is established, one set or the other is used for monitoring, not both.
• Transferrin as a nutrition marker plus a full iron workup. When transferrin is ordered to assess malnutrition, other iron studies are not needed unless deficiency or overload is also suspected.
• A repeat after a normal result when nothing about your condition has changed.

(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 $6.47 for serum iron and $8.74 for TIBC, $15.21 for the pair, and $12.76 for transferrin. You owe zero.

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

Quest’s own test directory flags iron and TIBC, and transferrin, as “subject to a Medicare Limited Coverage Policy” that “may require a signed ABN when ordering.” If iron studies are on your order without a qualifying diagnosis, or in a redundant combination, 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:

1. 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 iron and TIBC, it pays the lab $15.21 for the pair.
2. Ask which codes are on the order. If it lists iron, TIBC, transferrin, and ferritin, ask your doctor whether all four are needed on the first round; the policy says they usually are not, and the extra ones are the ones most likely to be denied.
3. Know the direct prices: iron and TIBC together sell for $5 at Jason Health (jasonhealth.com, plus their flat $18 lab-collection fee per order, so $23 all in) and for $53.10 at Quest’s consumer site (questhealth.com, plus a $6 physician fee), where they come bundled with ferritin. The full table is above. Same certified labs, same blood draw.

Before you sign the pad, 60-second checklist

1. Ask: “Can you print what I’ll owe if Medicare doesn’t pay?”
2. Ask your doctor: “Is there a finding, like my blood count or a bleeding problem, that makes this test medically necessary, and do we need all of these codes?”
3. Compare the printed price to the direct-purchase prices before deciding how to proceed.

What counts as a “normal” iron panel

Start with the ranges printed on your own report. Published ranges exist for these tests, they differ by sex and by lab, and every source says to use your own lab’s range.

• The MedlinePlus Medical Encyclopedia gives serum iron of 59 to 158 mcg/dL for men and 37 to 145 for women, TIBC of 171 to 505 for men and 149 to 492 for women, and iron saturation of 20 to 50 percent for men and 15 to 45 percent for women, adding that “normal value ranges may vary slightly among different laboratories.”
• Cleveland Clinic gives a general TIBC range of 240 to 450 mcg/dL and says laboratories “often have different reference ranges.”
• For transferrin, Labcorp’s reference interval for adults 18 to 80 is 177 to 329 mg/dL for men and 192 to 364 for women, and Quest’s is 188 to 341 mg/dL. Two major labs, two different ranges, for the same test.

None of the sources we checked gives a treatment target for any of these tests, so there is no “clinical target” to add here. The policy itself notes that inflammation and chronic disease change iron, TIBC, and ferritin in ways that make them hard to read, and Labcorp’s own guidance is that iron deficiency is shown by low iron, high TIBC, and low saturation together, not by any one number.

(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 blood count and your history.

Quick questions people ask

Is an iron panel the same as a ferritin test? No. Ferritin measures iron in storage; serum iron measures iron in circulation right now; TIBC and transferrin measure the carrying capacity. They are different codes with different prices, and Medicare’s policy expects your doctor to pick the set that fits the question rather than order all of them at once.

Do you have to fast for an iron test, and should it be in the morning? Yes to both, unless your doctor says otherwise. Medicare’s own policy says iron studies are best done fasting, in the morning, without medications that affect iron. Quest’s directory says iron values drop about 30 percent over the course of a day. MedlinePlus mentions a possible 12-hour fast; Cleveland Clinic says some providers require it and some do not. Our fasting guide explains what fasting means and what you can still drink.

Should you stop iron pills before the test? Ask your doctor, and do not stop a prescribed medicine on your own. Cleveland Clinic suggests avoiding iron supplements for 12 hours before a TIBC test, and Labcorp says the sample should be drawn before any iron treatment or transfusion and at least four days after a transfusion. Birth control pills and estrogen can also affect the results.

What does a high or low TIBC mean? In general terms, a high TIBC goes with low iron supplies (iron deficiency, late pregnancy), and a low TIBC goes with inflammation, liver disease, malnutrition, low blood protein, and some other anemias. Which of those applies to you is your doctor’s reading, not the number’s.

How long does an iron panel take? The blood draw takes minutes, and results are typically back in one to two business days, direct-purchase orders included.

Sources and data dates

Medicare payment amounts: CMS Clinical Laboratory Fee Schedule, 2026 Q3 file (national rates for 83540, 83550, and 84466). Coverage rules: CMS Medicare Coverage Database, NCD 190.18 (Serum Iron Studies), a national policy identical in every state, and the same text in the NCD Manual, Chapter 1, Part 3. Test descriptions, preparation, and ranges: MedlinePlus (Iron Tests; Serum iron test; Total iron binding capacity), Cleveland Clinic (Iron Blood Tests; TIBC), Quest tests 7573 and 891, Labcorp tests 001321 and 004937. 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.