Can you test your iron levels at home?
Yes, with a finger-prick kit a lab tests. But don’t judge it by the line called iron. Ferritin shows your stores, and most labs put the low line somewhere from 15 to 30.
On this page
Can you test iron levels at home?
Yes. You prick your finger, fill a small tube and post it to a lab. One NHS lab kit checks haemoglobin, ferritin, transferrin saturation, active B12 and folate for £49 (price checked November 2026).
Results usually come 24 to 48 hours after the lab gets your sample. The kit is for adults over 18 only.
You can’t check iron without blood. Tiredness is the classic sign, but it has many other causes, such as an underactive thyroid, depression and burnout.
| Option | Cost | What you get |
|---|---|---|
| GP blood test | Free on the NHS | A full blood count. Your GP looks for the cause too. |
| Home finger-prick kit tested in an NHS lab | £49 (adults over 18) | Haemoglobin, ferritin, transferrin saturation, B12 and folate. |
| Checking your symptoms | Free | A reason to test. It can’t tell you your iron. |
Sources: NHS; Monitor My Health; Al-Naseem 2021
Think you might have low iron? The NHS says to see a GP. A home kit suits you if you’d rather test first and take the result with you.
Weighing up the two? See home blood test vs GP.
Which line on a home iron test matters?
Look for ferritin first. Some kits also show a line called iron, but it swings through the day and shouldn’t be used to diagnose low iron.
| Line | What it shows | Low means |
|---|---|---|
| Ferritin | How much iron you have stored. The most useful line. | Below 30 µg/L is generally low. Below 15 is a sign of empty stores. |
| Haemoglobin | Whether you have anaemia, meaning too few working red cells. | Below 130 g/L in men, or below 120 in women who aren’t pregnant. |
| Transferrin saturation | How much iron is moving in your blood. | Low can suggest iron deficiency. One NHS lab uses below 16%. |
| Serum iron | Iron in your blood at that moment. | Not used to diagnose. It changes through the day. |
Sources: BSG; Monitor My Health; Al-Naseem 2021
That top line is your ferritin. Gut doctors call it the single most useful marker of iron deficiency anaemia.
Your stores can run low while haemoglobin is still normal. See low ferritin with normal haemoglobin, and more on transferrin saturation and serum iron.
What ferritin level is low?
Below 15 µg/L is a sign your stores are empty. Below 30 is generally a sign of low stores. So most labs set their low line somewhere from 15 to 30.
- Below 15 µg/LA sign of empty stores.
- 15 to just under 30 µg/LGenerally low stores.
- 30 up to 150 µg/LUsually not low, unless inflammation is raising it.
- Above 150 µg/LLow iron unlikely, even with inflammation.
Sources: BSG; Al-Naseem 2021
Think of ferritin as a fuel gauge. 15 is the warning light, and below 30 you’re already running low.
One NHS lab kit only flags ferritin below 15. So a 22 won’t be flagged. But in clinical practice, doctors can confirm iron deficiency below 30.
No warning light doesn’t mean a full tank. Read your number, not just the flag, and take a 22 to your GP.
Long-term inflammation, the body’s ongoing reaction in conditions like rheumatoid arthritis or bowel disease, raises ferritin. Then the low line moves up to 100, and transferrin saturation below 20% also points to low iron.
High instead? See high ferritin.
How to get an accurate home iron result
A good finger-prick sample reads close to one from your arm. In 296 people, the two showed no bias for ferritin and the other blood chemistry tests.
A Dutch study of 34 tests, iron and ferritin among them, found the two samples comparable for almost all. The catch is time. Ferritin in a finger-prick sample can drift after 24 hours at room temperature.
Five steps for a home iron test you can trust
- Take the test first thing in the morning, before you eat.
- Skip any supplements that day until your sample is done.
- Drink water before you start, as the lab advises.
- Post it the same day, Monday to Thursday, so it doesn’t sit over the weekend.
- Have a long-term inflammatory condition? Check your kit includes transferrin saturation.
Sources: Monitor My Health; Maroto-García 2023; Al-Naseem 2021
First time pricking your finger? See how to do a finger-prick test and how accurate finger-prick tests are.
What to do after a low iron test at home
Take it to your GP, especially if you also have anaemia. Low iron with anaemia could mean hidden blood loss, especially from the gut, so the cause matters as much as the number.
What usually happens after a low home result
- 1
GP blood test
A full blood count. No need to prepare.
- 2
Find the cause
Heavy periods, pregnancy or bleeding in the gut are common causes.
- 3
More checks if needed
If the cause isn’t clear, a poo test for blood or a specialist.
- 4
Treatment
For anaemia, iron tablets for about 6 months, plus iron-rich food.
Source: NHS
Low iron without anaemia? The NHS lab kit suggests changes to your diet first.
The NHS lists meat, pulses, dried fruit, fortified cereals and dark-green leafy vegetables like kale. See how to raise iron with food.
Thinking of buying iron tablets? The NHS says 17mg or less a day is unlikely to cause harm. Take more only if a GP advises it, and keep them away from children.
Never stop or change a prescribed medicine without your prescriber. Already on tablets? See iron tablets not working.
When to speak to a GP
Book an appointment if:
- You think you might have iron deficiency anaemia. Signs include tiredness, shortness of breath, noticeable heartbeats, paler skin and headaches.
- Your home kit shows low iron and anaemia. The NHS lab recommends discussing it with your GP.
- You’re a man or past the menopause and have new iron deficiency anaemia. Gut doctors say camera tests of the stomach and bowel should generally be the first gut tests.
- Your ferritin is below 30. That’s generally a sign of low stores, even if your kit didn’t flag it.
- You take painkillers like ibuprofen or aspirin and your iron is low. They can cause bleeding in the gut.
Heavy periods are a very common cause. See blood tests for heavy periods and the ferritin blood test.