Vitamins & Minerals

Ferritin & Iron Test

Ferritin is the best single marker of your body's iron stores.

Ferritin is a protein that stores iron in your body — measuring it is the most reliable single test for iron deficiency. A full iron profile also measures serum iron, transferrin and transferrin saturation to distinguish low stores from other causes of low iron.

What it measures

Ferritin

The main store of iron in your body — low ferritin is the earliest sign of iron deficiency.

Serum iron

The amount of iron currently circulating in your blood.

Transferrin

The protein that carries iron around the body.

Transferrin saturation

How much of your transferrin is actually carrying iron.

TIBC

Total iron-binding capacity — your blood's ability to bind iron.

Why it matters

Iron deficiency is one of the most common nutritional deficiencies, particularly in women of reproductive age.
Ferritin can be falsely raised by inflammation, so a full iron profile is often more informative.
Symptoms of low iron include fatigue, breathlessness, pale skin and brittle nails.

How testing works

Order a finger-prick or venous iron profile from a UKAS-accredited lab.
Avoid iron supplements for 24 hours before testing for the most accurate reading.
Results are typically returned in 2–4 working days with a clinician-reviewed report.

Compare Ferritin & Iron 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.

Compare providers

Frequently asked questions

What ferritin level is considered low?

UK guidance typically considers ferritin below 30 µg/L as suggestive of iron deficiency, though some clinicians use a 50 µg/L threshold for symptomatic individuals. Always interpret against your lab's reference range.

Do I need to fast before an iron test?

Fasting is not strictly required for ferritin, but morning samples taken before food and supplements are preferred for consistency.

Related guides