Homocysteine is one billing code, CPT 83090, and one of the most aggressively marketed lab tests in the direct-to-consumer market. Search for its price and you land almost entirely on lab storefronts, each quoting a different number with a different fee structure underneath it. Medicare, meanwhile, pays $17.92 for it.
That contrast is the whole story of this page. This guide gives the fee-schedule floor, the real cash prices you can buy today, the B-vitamin tests it is usually ordered alongside, and the one thing that quietly triples the cost: buying homocysteine inside a cardiovascular panel instead of on its own.
What Does a Homocysteine Test Cost Without Insurance?
Prices below were read on September 4, 2026 from each seller’s own published page, plus the CY 2026 Q3 release of the CMS Clinical Laboratory Fee Schedule and the CMS Medicare Physician and Other Practitioners file (2024 claims, released May 21, 2026).
| What you are buying | Low | Typical | High |
|---|---|---|---|
| Homocysteine alone, Medicare rate (CPT 83090, 2026 CLFS) | $17.92 | $17.92 | $17.92 |
| Homocysteine alone, prepaid marketplace (MDsave, 133 providers) | $21 | $42 | $92 |
| Homocysteine alone, direct-to-consumer lab, all in | $75 (Walk-In Lab) | $79 (Labcorp OnDemand) | $81 (Quest) |
| Homocysteine alone, average charge submitted to Medicare (2024) | $152.61 | $152.61 | $152.61 |
| Vitamin B12 (82607) and folate (82746), Medicare rate each | $14.70 | $14.89 | $15.08 |
| Vitamin B12 plus folate bought as one retail test (Quest) | $88 | $88 | $88 |
| Methylmalonic acid (CPT 83921), Medicare rate to average submitted charge | $21.21 | n/a | $212.42 |
| Cardiovascular panel with homocysteine folded in (Walk-In Lab) | $185 | $185 | $185 |
Sources disagree on the low end and it is worth saying why. MDsave’s page reports a prepaid national average of $42 against an estimated national average of $79, which is a $37 saving on the same test at the same providers, and it lists individual prepaid prices from $21 to $92 across 133 participating providers. The direct-to-consumer labs cluster much tighter, $75 to $81 all in, because their prices are national list prices rather than per-facility deals. Both are real. Which one you can get depends on whether an MDsave provider operates near you.
The $152.61 row is not something anyone pays voluntarily. It is the average charge providers submitted to Medicare for 83090 across 261,096 services in 2024, against an average allowed amount of $17.54. Charges like that are the starting point on a self-pay statement if nobody asks for a discount, which is why the negotiation section below matters more on this test than on most.
What Drives the Price
Whether you buy the marker or a panel
This is the largest single factor. Homocysteine is not in a standard lipid panel, and the big advanced cardiac panels frequently exclude it too. Quest’s homocysteine page cross-sells its Advanced Heart Health Test Panel (with ApoB) at $215.00, and still sells homocysteine separately at $75.00, meaning the panel buyer who also wants homocysteine pays for both.
Marketplace panels take the opposite approach and fold it in. Walk-In Lab’s Heart Health #2 Essential panel, which bundles a lipid profile, a metabolic panel, kidney and liver markers, C-reactive protein, lipoprotein(a) and homocysteine, is $185.00. If homocysteine is the only marker you were after, that is roughly $110 of tests you did not ask for. If you wanted the whole workup anyway, the bundle is the better buy. Our lipid panel cost guide covers what the cholesterol half of those panels costs on its own.
The fee that is not in the headline price
Every direct-to-consumer lab needs a physician to sign the order, and they charge for it separately. Quest lists homocysteine at $75.00 and adds a $6.00 physician service fee at checkout. Walk-In Lab lists it at $69.00 and adds a $6.00 per-order physician fee. Labcorp OnDemand lists $79 with the order included. Compare the all-in numbers, $81, $75 and $79, not the shelf prices.
Note that Walk-In Lab’s per-order fee is charged once per order rather than per test, so adding a second marker to the same order does not add a second $6.00.
Coupon prices with expiry dates
Because this keyword is heavily advertised, several lab menus run rolling promotions. Walk-In Lab displayed a WORK15 code taking homocysteine to $58.65 through September 8, 2026 when this page was written. Promotional prices are real while they last, but they are not what you should benchmark against. Use the list price, and take the coupon if it is still live at checkout.
The B-vitamin workup it usually travels with
Homocysteine rarely gets ordered by itself. Under the 2026 CLFS, the related codes sit in a narrow band: vitamin B12 (82607) at $15.08, folate (82746) at $14.70, homocysteine (83090) at $17.92, and methylmalonic acid (83921) at $21.21. Four tests, all within $7 of each other at the fee-schedule level.
Retail does not respect that band. Quest sells a combined Vitamin B12 & Folate Test for $82.00 plus the $6.00 fee, roughly $88 for two tests Medicare values at $29.78 together. And methylmalonic acid is the outlier at the billed-charge level: providers submitted an average of $212.42 for 83921 in 2024 against a $20.72 average allowed amount, the widest ratio of the four. If a workup comes back with several of these codes on it, the total can run well past $400 at list even though the fee-schedule value of the whole set is under $70.
Where the sample is drawn
A lab-store price assumes you walk into a patient service center with the order already written. Run the same test through a physician office visit and the visit is billed on top, and run it through a hospital outpatient lab and you are on the hospital’s chargemaster instead of a retail menu. The test does not change. Our blood work cost guide covers how much of a lab bill is really the draw and the visit.
Cash Price vs. Insurance
Homocysteine is a good candidate for paying cash and never filing a claim. At $75 to $81 all in, the direct-to-consumer price is usually below what the same test contributes to an unmet deductible when it is billed at the $152.61 average submitted charge, and there is no coverage determination to argue about.
There is a real tradeoff. A test you buy yourself does not count toward your deductible, and the results land in your inbox rather than in your clinician’s chart unless you forward them. For a single marker on a $75 test that is usually an easy trade. For a $185 panel it is worth checking coverage first.
If the test was already run in a hospital or health-system lab and the bill has arrived, the cash-price path is different: you are asking for the self-pay discount after the fact rather than shopping in advance. Hospitals must post their standard charges including discounted cash prices, and our guide to hospital price transparency explains how to pull the file for the facility that billed you and check the 83090 line against it.
How to Pay Less
Buy the single marker unless you want the whole panel. The difference between $75 for homocysteine alone and $185 for a heart-health bundle is not a discount you are missing, it is nine additional tests. Decide which you actually want before you shop.
Compare all-in prices, not shelf prices. The $6.00 physician fee at both Quest and Walk-In Lab is easy to miss and it reorders the ranking: Walk-In Lab’s $69.00 beats Labcorp’s $79 on the shelf but the gap is $4, not $10.
Check a prepaid marketplace for your metro. MDsave’s $42 national average is roughly half the direct-to-consumer price, though its $21 to $92 spread means the answer depends entirely on which providers participate near you. Check the local price rather than trusting the average.
Benchmark before you pay a bill. The 2026 CLFS rate for 83090 is $17.92 and the national average allowed amount in 2024 Medicare claims was $17.54. Those numbers are the floor. Our fair price tool compares a quote against national figures, and if a bill arrives near the $152.61 average submitted charge, that is a list price you can ask to have reduced. Our medical bill negotiation guide covers the script.
Use a sliding-scale clinic if the visit is the expensive part. When the order requires an appointment you do not have, a federally qualified health center charges for the visit on a household-income scale and can draw the sample the same day. Our guide to free clinics and sliding-scale care explains eligibility.
Order related markers on the same requisition. Because Walk-In Lab’s physician fee is per order rather than per test, adding B12, folate or methylmalonic acid to the same order avoids paying the fee twice. If B12 is the real question, our B12 shot cost guide covers what treatment runs after testing.
Where This Test Sits in a Wider Workup
Homocysteine shows up in two very different contexts, and the price of everything around it differs accordingly. On the cardiovascular side it sits alongside a lipid panel and, sometimes, imaging: our calcium score test guide covers the scan that often gets ordered in the same conversation, and it costs many times more than the blood test.
On the nutritional side it sits with B12, folate, methylmalonic acid, ferritin, vitamin D and a complete blood count. Those are all cheap individually and expensive as an unpriced bundle, which is the pattern worth watching. If a lab order has six or eight codes on it, ask for the price of the order rather than the price of the test.
The bottom line: the marker itself is a $17.92 test that retails for $75 to $81 and gets billed at $152.61 when nobody asks. Buy it alone, compare all-in prices, and check any bill against the fee schedule before paying it.