Best vitamin D tests compared.

Everlywell's Vitamin D Test is the cleanest single-marker at-home buy on the U.S. market in 2026 — $49 for a finger-prick 25(OH)D collection kit, processed at a CLIA-certified partner lab, with a result PDF reviewed by a physician before release. The kit lands in two to three business days, takes about five minutes to collect, and the result follows in five to seven days. The dashboard tracks readings across time, which matters if you plan to retest after starting a supplementation protocol.

What we like: onboarding and price are unusually well-balanced. The kit instructions are unambiguous, the collection device is forgiving, and the physician sign-off gives the result a layer of clinical legitimacy without a $90+ price tag. For a reader who has never tested vitamin D and just wants a clean baseline number, this is the lowest-friction option of the four reviewed here.

What we do not like: the included interpretation is minimal. The PDF tells you whether you fell into deficient, insufficient, or sufficient categories per standard U.S. cutoffs, but it does not contextualize the number against your symptoms, season, or supplementation history. A LetsGetChecked nurse call would do more on a flagged result, but the gap costs $40 more. Finger-prick collection is also occasionally finicky — Everlywell reships failed kits at no cost.

Best for: first-time vitamin D testers, women starting or adjusting a supplementation protocol, anyone living in a northern U.S. latitude who wants to confirm their winter reading. Worth discussing flagged results with a qualified healthcare provider before starting a high-dose protocol.

Quest's direct-access 25(OH)D test is the cheapest reliable vitamin D read in the U.S. consumer market — $30 to $50 depending on whether you go through Quest Health, MyLabResults, or one of the discount marketplaces that resell Quest tests. The accuracy is identical to a physician-ordered draw because it is the same lab, the same equipment, and the same reference ranges. You walk into a Quest draw station, a phlebotomist takes blood, and the result lands as a PDF in one to three business days.

What we like: the price-to-accuracy ratio is the best in this category. A venous draw avoids the small but real variance of finger-prick collection, the turnaround is the fastest of the four, and the reference range is the one your primary care doctor uses. For a reader who has tested before, knows roughly what they want, and just needs a baseline or a follow-up number, this is the cleanest path.

What we do not like: there is no clinical interpretation included. You receive the PDF and that is the product. For a first-time tester staring at a 25(OH)D of 22 ng/mL and not sure what to make of it, the Everlywell or LetsGetChecked format with included context is a better starting point. The Quest flow also expects you to handle the lab visit yourself — no kit, no shipping, just an appointment at a draw station near you.

Best for: cost-conscious readers, women already familiar with vitamin D testing who want a quick follow-up, anyone who lives near a Quest draw station. Speak with a qualified healthcare provider about the result before changing your supplementation.

Function Health includes 25(OH)D as part of its broader 110-plus marker comprehensive subscription. You will pay materially more than the Everlywell or Quest single-marker options, but you also get an MD review on every result, two annual venous draws, and the vitamin D number in context — calcium, magnesium, parathyroid hormone, and inflammation markers that interact with vitamin D in ways a standalone reading cannot show.

What we like: this is the only at-home product that reads vitamin D against the full mineral picture. A 25(OH)D of 24 ng/mL alongside a low calcium reads differently than the same number with normal calcium and normal magnesium — and the Function MD review flags the pattern without prompting. The twice-yearly cadence also captures the seasonal swing between late summer peak and late winter trough, which is the most useful comparison for vitamin D specifically.

What we do not like: this is overkill if vitamin D is your only question. If you want a vitamin D number and nothing else, Everlywell or Quest will answer that question for one-tenth the annual price. The subscription model is a real commitment — the value of Function compounds across multiple draws and multiple markers, not in a single vitamin D snapshot.

Best for: women who want trending vitamin D data alongside a comprehensive picture, anyone managing a chronic condition (autoimmune, bone density, fertility) where vitamin D status interacts with other markers. Discuss flagged results with a qualified healthcare provider before adjusting supplementation.

LetsGetChecked's Vitamin D test covers the same single marker — 25(OH)D — as Everlywell and Quest, at $89 with a finger-prick kit shipped to your door. The collection process is similar to Everlywell's: a lancet, a few drops onto a collection card, a prepaid return envelope. The structural difference is the included clinician follow-up: if the result is flagged as deficient or insufficient, a LetsGetChecked nurse calls within 24 hours to walk through what the number means and what next steps look like.

What we like: the nurse call is genuinely useful for a first-time tester. A 25(OH)D of 14 ng/mL is meaningfully deficient and the typical next step is a clinician conversation about a loading dose — a brief call from a nurse translates that into a clear plan instead of a panicky Google search. The dashboard tracks results over time, which matters if you plan to retest after starting a protocol.

What we do not like: the $40 premium over Everlywell buys context, not a better number. The 25(OH)D measurement itself is processed at the same kind of CLIA-certified lab. If you already have a clinician you trust and a clear plan for supplementation, the Everlywell or Quest path will give you the same number for less. The nurse call adds value mainly for first-time testers or readers without a primary care relationship.

Best for: first-time vitamin D testers who want a clinician on the other end, women without a regular primary care relationship who want guidance on a flagged result. Worth discussing any next-step protocol with a qualified healthcare provider before starting high-dose D3.