Health Tests · Labcorp OnDemand
Custom Thyroid Test, $247
$247 · no doctor visit needed
- Order online, walk into 2,000+ locations — no appointment
- Physician order included — no doctor visit required
- Results in your portal in days
Same certified lab your doctor uses. HSA/FSA accepted.
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Order online for $247, fast 12 hours, then walk into any of 2,000+ locations — no doctor's visit needed. Four markers in one draw — TSH, Free T3, Free T4, and TPO antibodies — with results in 1–2 days, and the honest limits on what the full panel can tell you.
The short version
$247, one fasting walk-in visit, results in 1–2 days
The Custom Thyroid Test ($247) is the full thyroid panel: TSH and Free T4, the two markers clinicians check first, plus Free T3 and TPO antibodies, the two that answer the follow-up questions. Order online, fast 12 hours, walk in for the draw, results in 1–2 days. It is a screening snapshot, not a diagnosis: it says which markers sit high or normal, not whether you have thyroid disease.
Shopping links on this page go directly to Labcorp OnDemand. We don't earn a commission on orders.
Price
| Test | Price | |
|---|---|---|
| Custom Thyroid Test | $247 | Order now → |
Prices checked Nov 11, 2026. HSA/FSA eligible. Self-pay; insurance not billed.
What the four markers measure
Four markers, one draw. TSH (thyroid-stimulating hormone) is made by the pituitary; it rises when the thyroid underproduces and falls when it overproduces, and it is usually the first marker clinicians look at. Free T4 is the main hormone the thyroid produces; low Free T4 with high TSH is the classic hypothyroid pattern. Free T3 is the active form of the hormone — the version your cells actually use — and it answers the conversion question: whether the T4 your thyroid makes is being turned into usable T3. TPO antibodies are the autoimmune marker: elevated levels suggest the immune system is attacking the thyroid, which is the mechanism behind Hashimoto’s, the most common cause of hypothyroidism. No single number tells the story; clinicians read the pattern across all four together.
Why four markers instead of two
The two-marker test — TSH plus Free T4 — is what clinicians check first, and for many people it is enough: a normal TSH with a normal Free T4 is reassuring, and an abnormal TSH points at the next step. The extra two markers answer the questions the first two leave open. Free T3 matters when TSH and Free T4 look normal but symptoms persist — a conversion problem shows up in T3, not in TSH. TPO antibodies matter when the question is why: a positive antibody result points at autoimmunity as the cause, which changes the conversation from “your thyroid is underactive” to “your immune system is attacking your thyroid,” and that distinction shapes follow-up. If you have a family history of autoimmune thyroid disease, or symptoms despite a normal TSH, the four-marker panel is the test that asks the fuller question. If you only want the routine screen, the two-marker test is the cheaper question.
The math: the bundle, the pieces, or the two-marker test?
The honest math is unusually clean here: the three components that make up this panel — the Free T3 test, the two-marker standard test, and the TPO antibody test — bought separately list for exactly the same total as the bundle. So the bundle is not a discount play — it is a one-visit play: one order, one fast, one draw, one report instead of three of each. Buy the bundle when you want all four markers. Buy the two-marker test when the routine screen is the question and the extra markers are not. Buy a single marker when only one number is missing — a TPO antibody test on its own, for example, when TSH and Free T4 are already known. The wrong way to use this panel is as a fishing expedition with no question in mind — four numbers with no follow-up plan are just four numbers.
Reading the results: four numbers, one pattern — and their honest limits
Your report prints each marker against the lab’s own reference range — read the numbers there, not against figures from the internet. The patterns are what matter: high TSH with low Free T4 is the classic hypothyroid picture; low TSH with high Free T4 points the other way; normal TSH with low Free T3 suggests a conversion question; positive TPO antibodies with a normal TSH suggest early autoimmunity worth watching. The honest limits: a panel cannot diagnose thyroid disease on its own. TSH fluctuates with illness, time of day, and some medications, so one abnormal reading is not a diagnosis. Elevated TPO antibodies make Hashimoto’s more likely, but diagnosis also weighs symptoms, exam, and sometimes ultrasound — the test is a clue, not a conclusion. And a normal result does not rule out problems if symptoms exist; an abnormal one is a reason to talk to a clinician, not to start or stop medication on your own.
These four markers screen for thyroid problems; they do not diagnose thyroid disease. Abnormal results deserve follow-up with your healthcare provider, who reads them against your history and decides what, if anything, changes.
Who should consider it — and who should skip it
This panel fits people who want the full thyroid picture in one visit: people with symptoms despite a normal TSH, people with a family history of autoimmune thyroid disease, and people who want a baseline they can track over time. It is the wrong purchase if you only want the routine screen — the two-marker test is the cheaper question in that case. It is also the wrong purchase if you are managing a known thyroid condition: then your testing should run through your clinician, who can order the right markers and read them against your history. And if you take thyroid medication, talk to your healthcare provider before ordering — the medication itself changes what the numbers mean, and the draw may need timing around your dose.
How walk-in thyroid testing works
You order the test online, then visit a patient service center for a standard venous blood draw — no doctor’s order, no appointment, and no insurance needed. The prep rules that matter: fast for 12 hours before the sample collection (no food or drink, except water), avoid alcohol for 24 hours before the test, and stop taking biotin for 72 hours before the draw — biotin supplements, common in hair and nail formulas, can falsely skew thyroid immunoassays. If you take thyroid medication, consult your healthcare provider before taking this test. Results typically post to a secure portal 1–2 days after your sample arrives at the lab. HSA/FSA accepted. Testing is performed in a CLIA-certified clinical laboratory. The test must be taken by the purchaser, and it is available to adults 18 to 100. A 20% off promo code (MARKER20) is currently running — check the product page for the current price before ordering.
Common questions
Do I need to fast before this test?
Yes. Fast for 12 hours before the blood draw — no food or drink except water. Avoid alcohol for 24 hours before the test, and stop taking biotin supplements for 72 hours before the draw — biotin can falsely skew thyroid immunoassays. If you take thyroid medication, consult your healthcare provider before ordering.
What does the Custom Thyroid Test add over the Standard Thyroid Test?
Two markers: Free T3 and TPO antibodies. The standard test measures TSH and Free T4 — the two markers clinicians check first. Free T3 answers the conversion question (whether T4 is being turned into usable T3), and TPO antibodies answer the why question (whether the immune system is attacking the thyroid, as in Hashimoto’s). If you only want the routine screen, the standard test is the cheaper question.
Can this test diagnose Hashimoto’s?
No. Elevated TPO antibodies make Hashimoto’s more likely, but diagnosis also weighs symptoms, exam, and sometimes ultrasound. The test is a clue, not a conclusion — and a positive antibody result with a normal TSH is a prompt to watch and follow up, not a diagnosis.
I take thyroid medication — can I take this test?
Talk to your healthcare provider first. Thyroid medication changes what the numbers mean, and the timing of the draw relative to your dose can matter. Your clinician can tell you whether to test, when to draw, and how to read the result against your treatment.
How often should thyroid levels be rechecked?
That depends on the result and your situation — a clinician usually repeats an abnormal TSH in weeks to months, and people on thyroid medication are typically monitored on a schedule their clinician sets. There is no one-size schedule; ask your clinician what cadence fits your situation.
Is this a home test kit?
No. This is an in-person blood draw at a patient service center — you order online, then walk in for the sample collection. Your results arrive through a secure online portal, typically 1–2 days after your sample reaches the lab.
Ready to order?
Get the full thyroid picture this week
Order the Custom Thyroid Test for $247 and walk in after a 12-hour fast this week — no doctor visit required.