Hormones

Thyroid Test

TSH, FT4, FT3 and thyroid antibodies — what each marker actually tells you.

A thyroid test measures the hormones that regulate your metabolism. A basic thyroid screen looks at TSH (thyroid stimulating hormone), while an advanced panel adds FT4, FT3 and thyroid antibodies to give a complete picture of how your thyroid is functioning.

What it measures

TSH

Made by the pituitary — the most sensitive single screen for thyroid problems.

Free T4 (FT4)

The main hormone produced by the thyroid gland.

Free T3 (FT3)

The active hormone that drives metabolism in your cells.

TPO antibodies

Raised in autoimmune thyroid conditions such as Hashimoto's.

Why it matters

Thyroid issues are common and often missed — symptoms overlap with stress, low iron and menopause.
An advanced panel is more informative than a TSH-only test when symptoms are present.
Thyroid results should always be interpreted by a clinician alongside symptoms.

How testing works

Order a thyroid panel as a finger-prick home kit or clinic blood draw.
Sample in the morning, ideally before any biotin-containing supplements.
Results are typically returned in 2–5 working days with reference ranges and clinician comments.

Compare Thyroid Test prices in the UK

Side-by-side comparison of CQC-regulated providers and UKAS-accredited laboratories. Transparent pricing, typical turnaround times and sample methods.

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Frequently asked questions

What does a high TSH mean?

A raised TSH usually suggests an underactive thyroid (hypothyroidism), as the pituitary increases TSH to try to stimulate more hormone production. A clinician will normally repeat the test and check FT4 before any diagnosis.

TSH-only or full panel?

TSH alone is fine for routine screening when you have no symptoms. If you have symptoms (fatigue, weight changes, hair loss, mood changes), a full panel including FT4, FT3 and antibodies is usually more informative.