Thyroid blood test in London: options, prices and how fast you get results

A private thyroid blood test in London starts at £39 for a TSH check at our Battersea clinic in Nine Elms, and most thyroid results come back within a day. A fuller panel with free T4 and free T3 costs £99. A complete panel that adds thyroid antibodies costs £129, with results in 2 days. A doctor reviews every result before you see it.

The right test depends on why you want it. For a first check when you have symptoms, TSH is the standard starting point. If you already take levothyroxine, or thyroid problems run in your family, a different test may suit you better. This guide explains the options, the prices and how quickly you can expect your results.

What does a thyroid blood test check?

• TSH (thyroid stimulating hormone) is made by the pituitary gland and tells your thyroid how hard to work. It is the most sensitive single test, and the one NICE recommends for a first check in adults with symptoms.
• Free T4 is the main hormone your thyroid makes. It is usually measured when TSH is outside the normal range, and to monitor treatment.
• Free T3 is the more active form. It is mainly useful when an overactive thyroid is suspected.
• Thyroid antibodies (TPO and thyroglobulin antibodies) show whether your immune system is targeting your thyroid. This is the most common cause of an underactive thyroid in the UK, often called Hashimoto's thyroiditis.

For help reading the numbers on your report, our separate article, Thyroid blood tests explained, is coming soon.

Which thyroid test should I choose?

A first check because of symptoms

Tiredness, weight gain, feeling cold, constipation, dry skin, thinning hair and low mood can all come from an underactive thyroid. Weight loss, a fast heartbeat, shakiness, feeling hot and anxiety can come from an overactive one. Our Thyroid Check (TSH) is a sensible first step. If you would rather have the main hormones measured in one go, the Thyroid Check Plus adds free T4 and free T3.

A family history, or questions about Hashimoto's

Thyroid Complete (incl. Hashimoto's) measures TSH, free T4, free T3 and total T4, plus TPO and thyroglobulin antibodies. Positive antibodies with a normal TSH do not need treatment, but they do mean you are more likely to develop an underactive thyroid in future, so your doctor may suggest checking TSH from time to time.

You already take levothyroxine

The Thyroxine Monitoring Check measures TSH and free T4, the tests used to check your dose. NICE suggests checking TSH every 3 months after a dose change until it is stable, then once a year. Book your blood test for before your morning dose.

Thyroid and other causes of tiredness

Low iron, B12 and folate cause many of the same symptoms as an underactive thyroid. Thyroid Complete + Iron & B12 tests for all of these together. If you want a general health check as well, our Full Body Health Check includes TSH and free T4, and there are versions with a fuller thyroid panel added.

How much does a thyroid blood test cost in London?

These are our current prices. There is no separate clinic fee, and you pay at your appointment.

For a home visit, add £80 to the price of your tests. Single tests, such as TPO antibodies on their own, are listed in the A to Z of blood tests.

How fast will I get my results?

Your sample goes to the laboratory the same day it is taken. Thyroid tests without antibodies are usually back in 1 day, and panels that include antibodies take 2 days. A doctor reviews your results before they are released to you, so allow a little time for that. Each test shows its expected time when you book, and our guide to fast blood test results in London explains more about turnaround.

How do I prepare for a thyroid blood test?

• Biotin: stop biotin (vitamin B7) for 48 hours before your test, including hair, skin and nail supplements that contain it. Biotin can interfere with the way some thyroid tests are measured and give misleading results.
• Levothyroxine: have your blood taken before your morning dose, then take it as usual afterwards.
• Fasting: not needed for thyroid tests on their own. If your thyroid test is combined with the Full Body Health Check, fasting is preferred, so book a morning appointment and have water only from midnight.
• Illness, pregnancy and medicines: a recent illness, pregnancy and some medicines can affect thyroid results. Tell us when you book, and the reviewing doctor will take this into account.

Where to get tested

• Clinic: 28-29 Wilcox Close, Nine Elms, Battersea, London SW8 2UD, inside the Medirex Pharmacy building
• Nearest stations: Nine Elms (Northern line) and Vauxhall (Victoria line and National Rail)
• Home visits: £80 on top of your tests, covering Zone 1, Battersea, Clapham, Balham and nearby
• Laboratory: The Doctors Laboratory (TDL), UKAS accredited
• Payment: book online and pay at your appointment

Not sure whether it is your thyroid or something else? Symptoms often overlap, so our guides to feeling tired all the time and menopause blood tests may also help.

What happens with your results

A GMC-registered doctor reviews every result and adds a comment before you see it. Reference ranges vary between laboratories, so your report shows the range used for your test. If anything needs treatment or follow-up, a doctor contacts you directly. You can also book a doctor's consultation to go through your results, and share them with your NHS GP if you would like to. See all our thyroid blood tests to choose the right one for you.

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