Specialist marker · Vitamins

Red cell folate test in the UK

A red cell folate test measures folate stored inside red blood cells, reflecting your intake over the last 2 to 3 months. Serum folate, the standard test, swings with what you ate in the last few days. Red cell folate is included in TrueVitals Signature (£799), read alongside serum folate, B12, active B12, homocysteine and red cell size (MCV).

Included in: SignaturePrice: £799 incl. drawWindow: Last 2 to 3 monthsResults: Up to 12 working days

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Serum folate vs red cell folate

Serum folate (in every panel)

Reflects the last few days
Rises quickly after a folate-rich meal or supplement
Good first check

Red cell folate (in Signature)

Reflects the last 2 to 3 months
Shows true tissue stores
Not fooled by one good week

Why folate matters

Folate is needed to make DNA and new cells, especially red blood cells. Too little causes large red cells and anaemia, tiredness and, in pregnancy, a higher risk of neural tube defects. Folate also works with B12 to keep homocysteine down.

Who it is worth testing for

Planning a pregnancy, to check stores are good before conception.
Large red cells (high MCV) on a previous test.
Raised homocysteine, to see whether folate is part of the cause.
Gut conditions such as coeliac disease, regular alcohol, or medicines that affect folate (methotrexate, some anti-epilepsy drugs).
Borderline serum folate that needs a clearer answer.

How it fits with your other results

Folate and B12 deficiency look alike in a blood count, and treating one while missing the other can be harmful. Signature reads red cell folate with serum folate, B12, active B12, homocysteine, MCV and the full blood count so the cause is clear.

Where to get a red cell folate test in the UK

Option	Includes it	Price	What else you get
TrueVitals Signature	Yes	£799 incl. draw	Red cell folate with serum folate, B12, active B12 and homocysteine among 230 biomarkers. Clinician-reviewed report.
TrueVitals Ultimate	Serum only	£399 incl. clinic draw	Serum folate, B12, full blood count and MCV; active B12 and homocysteine can be added.
NHS GP	Serum, if indicated	Free	Usually serum folate; red cell folate is rarely requested.

TrueVitals prices checked 5 November 2026. Every TrueVitals report is clinician-reviewed. Pay in instalments with Klarna or Clearpay. Signature is drawn at one of 70 Randox Health clinics; Ultimate at one of 103 partner clinics or with a home visit.

Be honest with yourself about what this test is for

Before taking folic acid for anaemia: make sure B12 has been checked too. High-dose folic acid can correct the blood count while a B12 deficiency continues to damage nerves.

A private panel is a good way to get a baseline, understand a result in context and track it over time. It does not replace your GP for symptoms, and anything that needs follow-up is flagged in plain words in your report.

Read alongside

Red cell folate on its own rarely tells the whole story. In TrueVitals panels it is reported with these related markers:

Serum folateVitamin B12 Active B12 HomocysteineMCVFull blood count

Frequently asked questions

Is red cell folate included in Ultimate?

No. Ultimate includes serum folate. Red cell folate is included in Signature.

Which is better, serum or red cell folate?

Serum folate is fine for a first check. Red cell folate is better for long-term stores because it is not affected by recent meals or a few days of supplements.

Do I need to stop folic acid before the test?

No. Keep taking it as normal and list it in your lifestyle quiz. Red cell folate shows your stores with your usual intake.

Can folate be too high?

High levels usually just reflect supplements or fortified foods. The main concern is high-dose folic acid hiding a B12 deficiency.

Do I need to fast?

Signature includes fasting markers, so an overnight fast with water only is advised.

How this page was written: by James Smillie, founder of TrueVitals, reviewed by the TrueVitals clinical review team, using NHS and laboratory reference sources. Ranges are typical values; your report uses your lab's own ranges. TrueVitals sells the panels named on this page, so we have stated plainly what this test cannot do. Last updated 5 November 2026.

Check your folate stores properly

Signature: 230 biomarkers including red cell folate, B12, active B12 and homocysteine, £799 including the draw. Clinician-reviewed report.

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