Function Health review (2026): is $365 for 160+ lab tests worth it?

Function Health review: the verdict

Function Health is the strongest lab-draw membership in the US right now. For $365 a year you get 160+ lab tests: about 100 at your first visit and 60+ at a follow-up three to six months later, all run by Quest Diagnostics, with a clinician's notes on the results. That works out to about $2.28 per test result, cheaper per marker than almost anything else you can buy without insurance.

The trade-off is the collection. You fast for 8 hours, go to a Quest patient service center (or pay for a home visit) and give roughly 35 to 85 mL of blood, which is several vials. You get two draws a year, not four or twelve. And member reviews point to slow, AI-heavy support when something goes wrong. We score Function Health 8.3 out of 10, the highest of the lab-draw services we cover.

If the draw is the part that puts you off, or you want to track a handful of markers every quarter, an at-home upper-arm test is the better fit. We cover that option at the end.

Would rather not go to a lab?SiPhox Health: 31 biomarkers including ApoB, Lp(a) and HbA1c from a needle-free upper-arm draw at home. $124 a test plus $25 shipping.

See SiPhox plans

What Function Health costs

The membership is $365 a year, billed once, which Function presents as "$1 a day". It was $499 until late 2025. Everything below was checked on Function's site on September 29, 2026 unless marked otherwise.

Our Function Health cost guide works out the real yearly bill with common add-ons, and our cost per biomarker calculator lets you compare it with any other service.

Read that chart with care. Function's $2.28 assumes you value all 160 results equally. If you only act on 20 of them, your real cost is $365 / 20 = $18.25 per result you use, which is more than SiPhox's $4.81 or Rythm's roughly $3.70 for a smaller panel you look at in full. The cheaper a service looks per marker, the more its value depends on caring about the long tail of the panel.

What Function tests

Function publishes its full list. The core membership covers these areas (counts are Function's own, and some markers appear in more than one area):

Two points worth knowing. First, the 160 figure includes the 20 urinalysis readings and several calculated values, so the count of distinct blood measurements is lower; that is normal across the industry, including at SiPhox. Second, the most talked-about extras are not in the base price: Galleri cancer screening, Alzheimer's markers, food sensitivities, mold and PFAS, extended heavy metals and scans are all paid add-ons.

Coverage is genuinely broad. Few services put ApoB, Lp(a), fasting insulin, homocysteine and thyroid antibodies in one membership. Our full body blood test guide explains which of these matter most.

How Function Health works, step by step

1. Join. You must be 18 or older and not pregnant. Function is not available in Rhode Island, Hawaii or Puerto Rico.
2. Book a draw. Choose one of 2,000+ Quest locations, or a paid home or office visit.
3. Fast and go early. Function asks for an 8-hour fast and recommends a morning appointment. Expect about 35 to 85 mL of blood, typically several vials; Wikipedia's summary puts it at 5 to 10 vials across the two visits.
4. First results. Function says the first batch starts arriving within 48 hours. Slower tests follow, and an independent review reports 7 to 10 business days for the full set, with the clinician summary later still.
5. Retest. A second, smaller panel of 60+ tests three to six months later tracks what changed.

Results and clinician notes

Function's pitch is that "clinicians review every result and flag issues". You get a dashboard grouped by body system, a written summary, a personalized protocol with food, supplement and lifestyle suggestions, and a biological age score twice a year. Function also added an AI model for health data in late 2025 and bought the supplement rating app SuppCo in May 2026.

Clinician notes are a real advantage over services that give you numbers alone. They are not the same as seeing your own doctor: Function does not prescribe for most results, and several one-star reviewers said the notes felt generic or left them unsure what to do next. Take any flagged result to your own doctor, who can repeat the test and act on it.

Function Health reviews and complaints

On September 29, 2026 Function had a 4.5 out of 5 rating from about 2,990 Trustpilot reviews: 74% five-star and 6% one-star. The praise centers on the breadth of testing, easy scheduling, and clear, actionable reports.

We read the 20 most recent one-star reviews (July to September 2026). One was a misfiled positive review; the other 19 break down like this:

There is also medical criticism of the model itself. Some doctors argue that testing 160 markers in healthy people produces false alarms and anxiety, and McGill's Office for Science and Society has challenged some of the company's heavy-metal claims. That is worth weighing: more markers means more chances of a result slightly out of range that means nothing. In January 2026 Function sued rival Superpower over its advertising claims; see our Superpower review for what that case alleges.

Function Health pros and cons

How we scored Function Health

For comparison, SiPhox Health scores 7.6 on the same method (full SiPhox review): it loses to Function on markers per dollar and wins on collection.

Who Function Health suits

• Buy it if you want the widest possible baseline once or twice a year, you live near a Quest center, a blood draw does not bother you, and you value a clinician's notes.
• Look elsewhere if you avoid needles or faint at draws, you live far from a Quest location or in Rhode Island or Hawaii, you want to recheck a few numbers (ApoB, HbA1c, testosterone, TSH) every quarter, or you are on a treatment such as GLP-1 medication or TRT that needs regular monitoring.

Is Function Health worth it? Four common cases

One practical tip if you join: book the first draw early in the morning after the full 8-hour fast, drink water, and ask for an itemized receipt at once if you plan to claim it from an FSA. Several one-star reviews were about receipts and renewals rather than the testing itself.

Which service fits which goal

The at-home alternative: SiPhox Health

SiPhox Health solves the three things Function cannot. There is no needle and no lab visit: you press a small EasyDraw device onto your upper arm at home, it collects blood in about five minutes, and you ship it back cold overnight. You can test monthly, quarterly or every six months, and switch panels each time. And it is sold per test, so you are not paying for 160 markers when you only want to track 30.

Be clear about what you give up: fewer markers per year, no included clinician notes, and a slower turnaround. Capillary samples also fail more often than venous ones, so follow the warm-up steps in our EasyDraw guide. For a direct head-to-head see SiPhox vs Function Health, and for the whole field see our Function Health alternatives.

Most people start here

Longevity Essentials

$124 + $25 shipping per test

31 biomarkers per test

The default panel: heart, metabolic, hormone and inflammation markers in one draw.

Check price

Heart & Metabolic

$124 + $25 shipping per test

28 biomarkers per test

Lipids plus kidney and liver function: the panel for cardiovascular and metabolic risk.

Check price

Ultimate 360

$249 + $25 shipping per test

62 biomarkers per test

Everything on the four core panels plus iron studies, B12 and folate, GGT and PSA.

Check price

Test at home insteadNo fasting trip to Quest, no needle. Pick a panel, choose how often, switch any time. HSA and FSA accepted.

Check SiPhox price

Frequently asked questions