How to Remove Blood Stains From a Mattress (Fresh and Dried)

The Single Most Important Rule

What You'll Need

• Cold water (a bowl, a damp cloth, or a spray bottle)
• 3% hydrogen peroxide (the standard drugstore strength)
• Baking soda
• Mild dish soap
• Several clean microfiber cloths or white towels
• Optional: an enzyme cleaner for stubborn or older stains

Fresh Blood: Step-by-Step

Speed helps. Fresh blood comes out far more easily than dried blood — the cleanup window is roughly the first hour.

1. 1Blot up as much blood as possible with dry towels. Press firmly. Don't rub — rubbing pushes blood deeper into the fabric.
2. 2Dampen a cloth with cold water and blot the stain from the outside in (working from edge toward center keeps it from spreading).
3. 3Mix two parts hydrogen peroxide, one part baking soda, and a drop of dish soap into a paste.
4. 4Spread a thin layer of the paste over the stain. You may see it bubble — that's the peroxide breaking down the proteins.
5. 5Let it sit for 30 minutes.
6. 6Blot away the paste with a clean damp cloth using only cold water.
7. 7Repeat once if a faint stain remains.
8. 8Blot dry with fresh towels and run a fan over the area until completely dry.

Dried Blood: Step-by-Step

Dried blood needs the same chemicals but longer dwell time. Older stains may take two or three passes.

1. 1Lightly mist the dried stain with cold water and let it soften for a few minutes.
2. 2Apply the hydrogen peroxide and baking soda paste generously.
3. 3Cover loosely with plastic wrap (slows evaporation and keeps the paste working longer).
4. 4Let it sit for at least one hour. Older stains can be left longer — up to several hours.
5. 5Remove the wrap, blot away with cold water and a clean cloth.
6. 6If a stain remains, apply an enzyme cleaner for a second pass. Pet-formula enzyme cleaners work as well on dried blood as they do on urine.
7. 7Cover with baking soda for 30 minutes, vacuum, then air-dry with a fan.

Specific Situations

What Not to Use

• Hot or warm water — sets the protein and bonds it to the fabric permanently
• Bleach — too harsh for mattress covers and foams, and it doesn't actually work on protein stains (it can fix them in place)
• Ammonia — damages mattress fabric and creates fumes; also doesn't break down proteins effectively
• Saliva or enzymatic toothpaste tricks from internet folklore — they technically contain proteases but in too-small quantities to do meaningful work on a real stain

Peroxide Cautions

Hydrogen peroxide is the most effective cleaner for blood on a mattress — but it can lighten some colored or patterned fabrics. Always test on a hidden area first (the underside of the mattress, or a corner that sits under the box spring is ideal). For white or cream-colored mattress covers, 3% peroxide is generally safe. For dark or patterned covers, switch to an enzyme cleaner and skip the peroxide.

When the Stain Won't Come Out

Some dried blood stains — especially ones that have been hit with hot water or set for weeks — won't fully come out. That's a cosmetic issue more than a functional one. The mattress still performs fine for sleep. The bigger consequence is that visible staining voids most manufacturer warranties, so install a waterproof protector immediately to preserve any remaining warranty coverage.