Blood Testing · Coming Soon
Full Blood
Count
One of the most informative tests in medicine. A Full Blood Count analyses your red cells, white cells, and platelets — giving a detailed snapshot of your health, energy, immune function, and more. Coming soon to The GP Service.
Licensed UK clinicians
Results within 24 hours
Clinician-reviewed results
Overview
What Is a Full Blood Count?
A Full Blood Count (FBC) is one of the most commonly requested blood tests in medicine — and for good reason. In a single sample, it gives a detailed analysis of the three major types of cells that circulate in your blood: red blood cells, white blood cells, and platelets. Each tells a different part of the story of your health.
Red blood cells carry oxygen from your lungs to every tissue in your body. White blood cells form the front line of your immune system. Platelets are responsible for clotting, preventing excessive bleeding when blood vessels are damaged. An FBC measures not just the counts of these cells, but their size, shape, and characteristics — giving clinicians a window into conditions ranging from simple iron deficiency anaemia to infection, inflammation, clotting disorders, autoimmune disease, and haematological malignancies.
It is often the first test ordered when someone presents with fatigue, unexplained weight loss, recurrent infections, unusual bruising, or a general sense that something is not right — because it casts a wide and informative net across many possible causes.
An FBC is also used routinely to monitor the effects of certain medications, assess the impact of chronic disease on the blood, and as part of pre-operative screening. It is a foundational test that underpins a large proportion of clinical decision-making in general practice and hospital medicine alike.
Coming Soon to The GP Service
We are launching Full Blood Count testing shortly — including clinician-reviewed results, same-day consultation to discuss findings, and onward management where needed. Register above to be notified as soon as it goes live.
What Gets Measured
What Does a Full Blood Count Include?
A standard FBC report contains between 15 and 20 individual values, grouped by cell type. Understanding what each component measures — and what it means when it falls outside the normal range — helps you make sense of your results.
Red Blood Cell Parameters
Haemoglobin
Normal: 120–160 g/L (women) · 130–170 g/L (men)
The protein in red blood cells that carries oxygen. Low haemoglobin = anaemia. High haemoglobin may indicate dehydration, lung disease, or polycythaemia.
The protein in red blood cells that carries oxygen. Low haemoglobin = anaemia. High haemoglobin may indicate dehydration, lung disease, or polycythaemia.
Hb
Red Blood Cell Count
Normal: 3.8–5.2 ×10¹²/L (women) · 4.3–5.7 ×10¹²/L (men)
The total number of red cells per litre of blood. Used alongside haemoglobin to characterise the type and severity of anaemia.
The total number of red cells per litre of blood. Used alongside haemoglobin to characterise the type and severity of anaemia.
RBC
Mean Cell Volume
Normal: 80–100 fL
The average size of red blood cells. Low MCV (small cells) suggests iron deficiency or thalassaemia. High MCV (large cells) suggests vitamin B12 or folate deficiency.
The average size of red blood cells. Low MCV (small cells) suggests iron deficiency or thalassaemia. High MCV (large cells) suggests vitamin B12 or folate deficiency.
MCV
Haematocrit
Normal: 36–46% (women) · 40–52% (men)
The proportion of blood volume occupied by red cells. A low haematocrit confirms anaemia; a high haematocrit may indicate polycythaemia or dehydration.
The proportion of blood volume occupied by red cells. A low haematocrit confirms anaemia; a high haematocrit may indicate polycythaemia or dehydration.
HCT
Mean Cell Haemoglobin
Normal: 27–33 pg
The average amount of haemoglobin per red cell. Low MCH means cells are under-filled with haemoglobin — characteristic of iron deficiency.
The average amount of haemoglobin per red cell. Low MCH means cells are under-filled with haemoglobin — characteristic of iron deficiency.
MCH
Red Cell Distribution Width
Normal: 11.5–14.5%
Measures variation in red cell size. A high RDW indicates cells vary significantly in size — seen in iron deficiency, B12 deficiency, and some haematological conditions.
Measures variation in red cell size. A high RDW indicates cells vary significantly in size — seen in iron deficiency, B12 deficiency, and some haematological conditions.
RDW
White Blood Cell Parameters
Total White Cell Count
Normal: 4.0–11.0 ×10⁹/L
The total count of all immune cells. Elevated in infection, inflammation, or blood disorders. Low counts raise concern about immune suppression or bone marrow problems.
The total count of all immune cells. Elevated in infection, inflammation, or blood disorders. Low counts raise concern about immune suppression or bone marrow problems.
WBC
Neutrophils
Normal: 1.8–7.5 ×10⁹/L
The most abundant white cell — the first responders to bacterial infection. A raised neutrophil count strongly suggests bacterial infection or steroid use. Low counts (neutropenia) increase infection risk significantly.
The most abundant white cell — the first responders to bacterial infection. A raised neutrophil count strongly suggests bacterial infection or steroid use. Low counts (neutropenia) increase infection risk significantly.
NEUT
Lymphocytes
Normal: 1.0–4.0 ×10⁹/L
Key players in viral immunity and immune memory. Elevated in viral infections and some leukaemias. Low in HIV, certain medications, and following chemotherapy.
Key players in viral immunity and immune memory. Elevated in viral infections and some leukaemias. Low in HIV, certain medications, and following chemotherapy.
LYMPH
Eosinophils
Normal: 0.04–0.44 ×10⁹/L
Involved in allergic responses and defence against parasites. Elevated eosinophils can indicate asthma, allergies, eczema, or a parasitic infection.
Involved in allergic responses and defence against parasites. Elevated eosinophils can indicate asthma, allergies, eczema, or a parasitic infection.
EOS
Platelets
Platelet Count
Normal: 150–400 ×10⁹/L
The cells responsible for clotting. Very low platelets (thrombocytopenia) can cause abnormal bruising or bleeding. Very high counts may indicate inflammation or, rarely, a bone marrow condition.
The cells responsible for clotting. Very low platelets (thrombocytopenia) can cause abnormal bruising or bleeding. Very high counts may indicate inflammation or, rarely, a bone marrow condition.
PLT
Mean Platelet Volume
Normal: 7.5–12.5 fL
The average size of platelets. Larger platelets are more active; elevated MPV alongside a low platelet count can help characterise the cause of thrombocytopenia.
The average size of platelets. Larger platelets are more active; elevated MPV alongside a low platelet count can help characterise the cause of thrombocytopenia.
MPV
Results Always Need Clinical Context
A single value outside the normal range does not automatically indicate a problem — ranges are population averages, and individual variation is significant. Results are most meaningful when interpreted alongside symptoms, medical history, and often repeat testing. When we launch FBC testing, every result comes with a clinician review, not just a printout of numbers.
Indications
When Do You Need a Full Blood Count?
A Full Blood Count is one of the most versatile investigations in general medicine. It is appropriate in a wide range of situations — both for diagnosing new symptoms and for monitoring known conditions over time.
Persistent Fatigue
Unexplained, ongoing tiredness is one of the most common reasons an FBC is requested — it screens for anaemia, infection, and haematological causes in a single test.
Suspected Anaemia
Pallor, breathlessness, palpitations, or dizziness may all indicate anaemia. An FBC confirms the diagnosis and the MCV helps identify whether it is iron, B12, or folate deficiency.
Recurrent or Prolonged Infection
Frequent infections, infections that take a long time to resolve, or an unusually severe infection may indicate an underlying problem with white cell production or function.
Unexplained Bruising or Bleeding
Easy bruising, prolonged bleeding from minor cuts, or unusual petechiae (pinpoint bruising) can all indicate a low or dysfunctional platelet count.
Unexplained Weight Loss
Significant unintentional weight loss alongside abnormal blood counts raises concern about a haematological malignancy and warrants prompt investigation.
Medication Monitoring
Several medications — including chemotherapy drugs, methotrexate, carbimazole, clozapine, and some antibiotics — require regular FBC monitoring due to their effects on bone marrow and blood cells.
Pregnancy
Anaemia is common in pregnancy as blood volume expands and iron demands increase. FBC is part of routine antenatal blood testing and is often repeated in the third trimester.
Routine Health Screening
An FBC as part of a general health check can identify subclinical anaemia, early signs of inflammation, or borderline counts that warrant monitoring before symptoms develop.
Pre-operative Assessment
Most surgical procedures require a baseline FBC to identify anaemia or clotting issues that could complicate surgery or recovery, and to establish a baseline for post-operative comparison.
The Process
What's Involved in Getting an FBC
A Full Blood Count is one of the simplest and least invasive investigations available. Here is what the process looks like end to end — as it will work when we launch this service.
1
Book Your Test
Request an FBC online in minutes — no GP referral required.
Choose a convenient phlebotomy location
Or request a home visit blood draw
No fasting required for a standard FBC
2
Give Your Sample
A simple venous blood draw — typically less than 5 minutes.
Small volume sample from a vein (usually the arm)
Processed by an accredited UK laboratory
Results typically within 24 hours
3
Review with a Clinician
Your results are reviewed by a licensed clinician, not just sent as a data file.
Plain-English explanation of every value
Flagged results explained in context
Onward management arranged where needed
Launching Shortly
We are finalising our laboratory partnerships and clinical workflow for Full Blood Count testing. We expect to launch within the coming weeks. Register at the top of this page to be notified as soon as it is available — early registrants will receive priority access.
Interpreting Results
What Can an Abnormal FBC Tell You?
An FBC result is most useful when abnormal values are interpreted together — not in isolation. The pattern of which values are raised or low, and by how much, usually points towards a specific diagnosis or category of diagnoses.
Pattern
What It Suggests
Common Causes
Low Hb + low MCV
Microcytic anaemia
Iron deficiency, thalassaemia, anaemia of chronic disease
Low Hb + high MCV
Macrocytic anaemia
B12 deficiency, folate deficiency, alcohol excess, hypothyroidism, some medications
Low Hb + normal MCV
Normocytic anaemia
Acute blood loss, haemolysis, anaemia of chronic disease, kidney disease
Raised WBC + raised neutrophils
Neutrophilia
Bacterial infection, inflammation, steroid use, stress response
Raised WBC + raised lymphocytes
Lymphocytosis
Viral infection (EBV, CMV), chronic lymphocytic leukaemia
Low WBC (especially neutrophils)
Neutropenia
Viral infection, B12/folate deficiency, medication side effect, bone marrow suppression
Low platelets
Thrombocytopenia
ITP, B12/folate deficiency, sepsis, liver disease, medication side effects
Raised platelets
Thrombocytosis
Iron deficiency, infection, inflammation, post-splenectomy, essential thrombocythaemia
Pancytopenia (all counts low)
Bone marrow failure
Aplastic anaemia, B12/folate deficiency, haematological malignancy, chemotherapy
An Abnormal Result Is a Starting Point, Not a Diagnosis
Most abnormal FBC results require further investigation before a diagnosis can be confirmed — whether that means a repeat test, additional blood tests (ferritin, B12, folate, reticulocytes), or referral to a specialist. When we launch this service, our clinicians will guide you through exactly what any abnormal result means and what the appropriate next steps are.
Why The GP Service
What Will Make Our FBC Service Different
There is no shortage of private blood testing options in the UK. Most will post you a results PDF and leave you to make sense of it alone. That is not how we are building this. Here is what will set our Full Blood Count service apart from the moment it launches.
Every result reviewed by a licensed clinician
Your FBC will not be returned as a raw data file. A licensed UK clinician will review every value in the context of your symptoms and history before your results reach you.
Plain-English explanations, not just numbers
Reference ranges mean very little without context. We will explain what each value means for you specifically — not just whether it sits inside or outside a population average.
Results within 24 hours
We are partnering with accredited UK laboratories to return results quickly. No waiting 5 working days or chasing a GP receptionist to find out if your bloods have come back.
Onward management included
If your results flag something that needs following up — a further test, a referral, or a prescription — we arrange it in the same consultation. You will never be told "something is abnormal" and left to figure out the next step yourself.
Joined up with your NHS care
We share results and clinical notes with your NHS GP where appropriate. Our service complements your existing care — it does not exist in a silo separate from the rest of your health.
From home, at a time that suits you
Book online, choose a convenient phlebotomy location or home visit, receive results and a clinician review — all without taking time off work or sitting in a waiting room.
Our Clinical Approach
How We Will Approach Your FBC Results
A number outside the reference range is the beginning of a clinical conversation, not the end of one. Here is what the process will look like from the moment your sample is taken to onward management being arranged.
You book and give your sample
Select a phlebotomy location or request a home blood draw. The appointment typically takes under 10 minutes. No fasting required for a standard FBC. Your sample is couriered to our accredited laboratory the same day.
Laboratory analysis — results within 24 hours
Your sample is processed by a UK laboratory. The full FBC panel — red cell parameters, white cell differential, and platelet indices — is analysed and the results are passed to your reviewing clinician.
Clinician reviews every value in context
A licensed clinician reviews your results alongside the reason for your test, your symptoms, and any relevant history. Values are not assessed in isolation — the pattern across the full panel, and what it means for you specifically, is what matters.
You receive a plain-English results summary
Your results are returned with a written explanation of every significant value. Normal results are confirmed clearly. Abnormal or borderline values are explained — what they suggest, how significant the deviation is, and what the likely causes are.
Follow-up arranged where needed
If your results indicate that further investigation is appropriate — additional blood tests, imaging, a specialist referral, or a prescription — we arrange this directly. You do not need to go back to your NHS GP and start the conversation again from scratch.
Results shared with your NHS GP
With your consent, your results and the associated clinical note are shared with your NHS GP, so they are part of your complete health record. If any findings are clinically significant, we will flag these to your GP proactively.
What If I Already Have FBC Results I Don't Understand?
You do not need to wait for our FBC service to launch if you already have blood results you want reviewed. Our clinicians can discuss existing results — from your NHS GP, a previous private test, or a hospital appointment — as part of a general health consultation, available now. Book a consultation
In the Meantime
What to Do While the Service Launches
If you are here because you are experiencing symptoms and need answers now, you do not have to wait. There are several routes available to you today through The GP Service, alongside registering for early access to our FBC.
Book a General Health Consultation
A licensed clinician can review your symptoms, advise on what testing is appropriate, and arrange an NHS or private blood test referral today — including an FBC if clinically indicated.
Get Existing Results Reviewed
Already have FBC results from your GP or a previous test but unsure what they mean? Book a consultation to have a clinician walk you through every value and advise on next steps.
Request a GP Blood Test Referral
If you need a blood test but cannot get an NHS appointment, our clinicians can issue a private laboratory referral for a range of tests including FBC, iron studies, B12, folate, and more.
Medication Monitoring Support
If you are on a medication that requires regular FBC monitoring — such as methotrexate, carbimazole, or clozapine — we can arrange testing and review results on an ongoing basis.
Fatigue or Anaemia Assessment
Persistent tiredness is one of the most common reasons an FBC is requested. If fatigue is affecting your daily life, book a consultation now to begin investigating the cause without waiting for the FBC service to launch.
Register for Early Access
Leave your details at the top of this page and we will notify you the moment FBC testing goes live — including any introductory pricing available to early registrants.
Full Blood Count testing — coming to The GP Service soon.
Register now and be the first to know when we launch. Our FBC service will include a clinician-reviewed result, a plain-English explanation, and onward management if anything needs following up — all without a waiting room.
Register for Early Access
No fasting required
Results within 24 hours
Clinician-reviewed — not just a data file
Secure & confidential
Licensed UK clinicians
Frequently Asked Questions
What does a Full Blood Count test for?
A Full Blood Count analyses the three main types of blood cells — red cells, white cells, and platelets — along with a range of sub-measurements including haemoglobin, mean cell volume, and differential white cell counts. It can identify anaemia (and its type and likely cause), infection, inflammation, clotting disorders, immune deficiencies, and haematological malignancies. It is one of the most informative single tests available in general medicine.
Do I need to fast before a Full Blood Count?
No — an FBC does not require fasting. You can eat and drink normally before the test. If your FBC is being taken alongside other tests that do require fasting (such as a fasting glucose, HbA1c, or lipid profile), you may be advised to fast for those, but the FBC result itself is not affected by food intake.
How quickly do Full Blood Count results come back?
Results from a private laboratory are typically available within 24 hours of the sample being received. NHS results take 2–5 working days in most cases. When we launch this service, we aim to return results with a clinician review within 24–48 hours of your sample reaching the laboratory.
What happens if my results are abnormal?
All results — normal or abnormal — will be reviewed by a licensed clinician before being returned to you. If any values fall outside the reference range, your clinician will explain what the finding means in the context of your symptoms and history, whether any further tests are needed, and whether any treatment or referral is appropriate. You will never receive a list of numbers without context.
Is an FBC the same as a Complete Blood Count (CBC)?
Yes — Full Blood Count (FBC) is the term used in the UK and most Commonwealth countries; Complete Blood Count (CBC) is the equivalent term used in the United States. Both tests measure the same parameters and analyse the same three cell lines. The reference ranges may differ slightly between countries and laboratories, but the underlying test is the same.
Can I request an FBC without seeing a GP first?
Yes — when this service launches, you will be able to request an FBC directly through The GP Service without a prior GP appointment or referral. Our clinicians will review your results and discuss them with you directly. If your results indicate something that requires referral to a specialist or liaison with your NHS GP, we will manage that on your behalf.
Will my results be shared with my NHS GP?
With your consent, yes. We strongly encourage sharing results and any associated clinical notes with your NHS GP so that your full health picture is available to whoever provides your care. If any results are particularly significant, our clinicians will advise you on the importance of informing your NHS GP and can write to them directly if appropriate.
When is this service launching?
We expect to launch Full Blood Count testing shortly. Register at the top of this page to be notified as soon as it goes live. Early registrants will receive priority access and will be informed of any introductory pricing before it is made public.
Medical Disclaimer: The information on this page is provided for educational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare professional with any questions you may have regarding a medical condition or medication. Never disregard professional medical advice or delay seeking it because of something you have read on this page. If you think you may have a medical emergency, call 999 or your local emergency services immediately.