Checks active B12 (holotranscobalamin), the form of vitamin B12 taken up and used by your cells, from an at-home sample. Suited to a quick, flexible check on B12 status, including for vegetarians and vegans, who are more at risk of low B12.
1 biomarker as listed by Blue Horizon Medicals.
This test measures active B12 (holotranscobalamin), the fraction of circulating B12 that your cells can actually take up and use, typically 10-30% of total B12. It's commonly used to assess B12 status, including in people following vegetarian or vegan diets, who get less B12 from food and are more likely to run low.
Within the Vitamin B12 test group we track, this one is priced close to the median: £45.25 against £46.00, a difference of about 2%. Medichecks and London Medical Laboratory offer the same single marker for £39, so it isn't the cheapest option, but it beats Randox Health (£46), Forth (£50), Better2Know (£55 and £170) and Bluecrest Wellness (£65) on price, while matching them on the single B12 marker tested.
It scores at the top of the scale for collection convenience, since you can use an at-home finger-prick kit or a Tasso autodraw device as well as a clinic or nurse visit, with results back within a day. It also scores well for results and follow-up, since a doctor reviews the result, and for documentation, since the biomarker, sample type, turnaround and collection options are all published clearly. Blue Horizon has traded since 2009, holds a Trustpilot score of 4.2 from 395 reviews, and uses UKAS ISO 15189 partner labs.
This suits anyone who wants a quick, doctor-reviewed check on active B12 with a choice of at-home or clinic collection, including vegetarians, vegans, or anyone wondering if fatigue could be linked to low B12.
If price is the only factor, Medichecks and London Medical Laboratory both offer the same single B12 marker for £39, £6.25 less. If you'd rather have a wider panel that includes B12 alongside other B vitamins, Blue Horizon's own Vitamin B Profile covers six B vitamins, though at a considerably higher price.
You can collect your own sample at home with a finger-prick kit or a Tasso autodraw device, or have a venous draw at a clinic or by a home nurse visit. The sample is tested for active B12, with results back within a day, and a doctor reviews the result before you receive it.
This at-home Active B12 test costs £45.25, close to the £46.00 median for the Vitamin B12 tests we track. It offers the fastest, most flexible collection in that group, at-home finger-prick, Tasso autodraw or a venous option, with results back within a day. Medichecks and London Medical Laboratory offer the same single marker for £39, so it isn't the cheapest, but the collection choice and one-day turnaround set it apart.
The listing publishes a detailed description, the full biomarker list, a stated turnaround, clear collection options, the sample type; it does not state what the report looks like.
A single-marker test measuring exactly what it sets out to; depth is not the point of this comparison group.
A finger-prick sample you take at home; with a venous or clinic option as well; a home nurse visit is offered; results in around 1 days, well ahead of the vitamins norm of 3.5.
Results are reviewed by a doctor; the provider does not describe the report format.
Trustpilot 4.2 from 395 reviews; accredited lab (UKAS ISO 15189 partner labs); trading 17+ years.
£45.25 against a comparison-group median of £46.00 (-2%).
Calculated 13 September 2026 from the facts we hold about this test and provider, using our published scoring formula. Scores are not hand-edited.
This test belongs to our Vitamin B12 test comparison group. See how it stacks up against equivalent tests from other providers.
Tied for cheapest single B12 test, with fast results
This test measures active vitamin B12 on its own, the form of B12 that is actually available for your body to use. It suits people with possible deficiency symptoms, such as fatigue, low energy or memory problems, or a diet or condition that raises their risk.
Flexible collection, price close to the group average
This blood test measures total vitamin B12, the standard marker for checking B12 status. It suits people who want a straightforward single-marker check rather than the added detail of active B12 or related markers.
Joint-cheapest B12 test in its comparison group
A single-marker blood test measuring vitamin B12, useful for checking deficiency risk, particularly on a plant-based diet.
Priced above the median for active B12 tests we track
A single-marker blood test measuring active vitamin B12, suited to people at risk of deficiency, including vegetarians and vegans.
At-home B12 test priced right at the group median
An at-home blood test measuring vitamin B12 levels, useful for vegans, vegetarians and anyone with symptoms of low energy or tiredness that could point to a deficiency.
Mid-priced B12 kit, well under Better2Know's clinic price
This at-home finger-prick test checks your vitamin B12 level, a nutrient needed for healthy blood and nerve cells. It suits people who want a quick, independent check for a B12 deficiency without a clinic visit.
Priciest B12 test in a group full of £39-55 options
A single blood test that measures your vitamin B12 level, useful if you want to check for a deficiency affecting energy, mood or nerve health.
Among the priciest B12 tests we compare, bar one
A single blood test measuring Vitamin B12, commonly used to assess levels relevant to nerve function and red blood cell production. Useful for vegans, vegetarians or anyone with absorption concerns.
Why Take the Vitamin B12 Test? Vitamin B12 is a vital nutrient that plays a crucial role in maintaining overall health.
Tied for cheapest single B12 test, with fast results
This test measures active vitamin B12 on its own, the form of B12 that is actually available for your body to use. It suits people with possible deficiency symptoms, such as fatigue, low energy or memory problems, or a diet or condition that raises their risk.
Flexible collection, price close to the group average
This blood test measures total vitamin B12, the standard marker for checking B12 status. It suits people who want a straightforward single-marker check rather than the added detail of active B12 or related markers.
Joint-cheapest B12 test in its comparison group
A single-marker blood test measuring vitamin B12, useful for checking deficiency risk, particularly on a plant-based diet.
Priced above the median for active B12 tests we track
A single-marker blood test measuring active vitamin B12, suited to people at risk of deficiency, including vegetarians and vegans.
