How to Get Blood Out of Carpet (Fresh and Dried Stains)

To get blood out of carpet, blot up as much as you can, then treat the spot with cold water only and keep blotting until no more colour comes off on the cloth. If a mark stays, use a weak solution of mild laundry detergent in water, rinse, and press the area dry. Never use hot water. Heat can set blood into the fibres for good.

That is the short answer, and it is the order Australian carpet maker Godfrey Hirst gives for blood in its synthetic carpet care guide. The rest of this guide covers how to stay safe while you clean, what to do when the blood has already dried, how wool carpet is different, and when it is time to stop and call a professional.

For other kinds of spills, see our complete guide to removing carpet stains.

Blood can carry infections, so health departments advise treating any blood spill as potentially infectious. SA Health recommends disposable gloves, cleaning up as soon as possible, putting used gloves and paper towel in a sealed plastic bag, and washing your hands well afterwards.

For carpet specifically, the Victorian Department of Health says a blood spill on carpet should be shampooed as soon as possible and that disinfectant should not be used on carpet. Steam cleaning can be used instead. That matches Godfrey Hirst's care guide, which warns that strong household chemicals such as bleaches, tile cleaners and mildew removers can permanently discolour carpet fibres.

If the spill is large, came from someone you do not know, or you are not comfortable cleaning it, leave it and get help. That is a sensible call, not an overreaction.

Godfrey Hirst's guide suggests warm, not hot, water for the detergent step. We keep the whole job cold on blood as the safer choice, because a stain that has not fully lifted can set if it warms up.

Dried blood is harder, but it is often still worth trying. The key is to rewet it slowly with cold water rather than attacking it.

1. Scrape off any crusty bits gently with a blunt knife or spoon, then vacuum them up.
2. Dampen the stain with cold water and leave it for 5 to 10 minutes to soften.
3. Blot, then repeat the cold water and detergent steps above.
4. Be patient. Two or three gentle rounds usually do more than one aggressive one.

If the mark has not changed after two careful attempts, stop. More scrubbing or stronger products at that point usually damage the carpet more than they help. An old blood stain that has bonded to the fibre is one of the harder stains to remove at home, and it often needs professional hot water extraction, which is what our carpet steam cleaning service uses.

Yes. Wool is a natural protein fibre, a little like blood itself, so products that break down protein can also harm wool. The Woolmark Company warns that much of the stain advice online is written for cotton or synthetic fibres and is not all suitable for wool. Its own advice is for wool clothing rather than carpet, but the principles carry over: remove the excess immediately, pre-test every treatment, and use small amounts.

If you do not know your carpet fibre, check your purchase paperwork or ask the retailer. Until you know, treat it like wool.

Over-wetting is easy to do when you are worried about a stain. The Carpet and Rug Institute's technical director has warned that excess wetting can cause carpet backing to delaminate, meaning the layers of the carpet start to come apart. Use a little liquid at a time and blot often.

You will see hydrogen peroxide recommended in a lot of blood stain guides. It can work, but it is a bleaching agent, so treat it as a last resort on synthetic carpet only and never on wool.

Even carpet cleaning machine maker Bissell says to test on a hidden area first to make sure the carpet is colourfast. If you try it, use standard 3% household strength, test it in a hidden spot, wait to check for colour change, and rinse it out afterwards. Never mix it with other cleaning products. If the carpet is expensive, dark, patterned or wool, skip it and ask a professional.

Call a professional carpet cleaner when:

• the blood has dried and two careful attempts have not shifted it
• the spill is large, or has soaked through towards the underlay
• the carpet is wool, or you do not know the fibre
• you are moving out of a rental and the carpet needs to pass the final inspection (see our end of lease cleaning)

Godfrey Hirst's guide says that if a stain does not respond to treatment you should call a professional carpet cleaner immediately, and it notes that stain removal can never be guaranteed. We agree with both points. Professional carpet steam cleaning uses controlled hot water extraction with a powerful vacuum, so the stain and the rinse water are pulled back out rather than left in the carpet.

Our team cleans carpet across Canberra and Queanbeyan. You can see what is included on our Canberra carpet cleaning page, or check our carpet cleaning prices before you book. If blood has landed on a fabric couch instead, our upholstery cleaning service can help.