Laundry Temperature Guide
Cold, warm or hot: a laundry temperature guide
Water temperature decides more about a wash than the detergent does — what comes out, what fades, what shrinks, and most of what the cycle costs to run. Every figure here is sourced, and the sources are at the bottom.
Cold is the default for most loads. About 90% of the energy a washing machine uses goes to heating water, so temperature is the single biggest lever on what a wash costs to run.
Use it for
- Everyday clothes with light or ordinary soil
- Dark and bright colours that bleed
- Delicates, activewear and anything with elastane
- Anything the care label marks cold
Watch out for
- Heavy body oils and grease lift less readily without heat
- Powder detergent can dissolve incompletely in very cold water
- It does not sanitise — see hot
Warm is the middle setting: more cleaning power than cold on oily soil, less shrinkage and fading than hot, and it still costs less to run than a hot wash.
Use it for
- Moderately soiled everyday laundry
- Synthetics and permanent-press items
- Light-coloured cottons
- Body oil on collars, cuffs and bedding
Watch out for
- Can still set protein stains — blood, egg, dairy — which need cold first
- New brights may bleed more than in cold
Hot is for hygiene and heavy soil, not for everyday laundry. It is the most expensive setting to run and the hardest on fabric.
Use it for
- Bed linen and towels when someone has been ill
- Cloth nappies and heavily soiled work clothes
- White cottons that have gone grey
- Fabrics the care label marks hot
Watch out for
- Shrinkage in cotton and wool, and faster fading
- Sets protein stains permanently
- Damages elastane, so not for activewear
- Most home machines do not reach true disinfection temperature — check the manual
By stain
| Stain | Start with | Why |
|---|---|---|
| Blood, egg, dairy, sweat | Cold | Protein. Heat cooks it into the fibre and sets it permanently. |
| Grease, oil, makeup, salad dressing | Warm to hot | Fat needs heat to soften before a surfactant can lift it. |
| Wine, coffee, tea, fruit juice | Cold, then treat | Tannin. Rinse cold first; hot water can set the colour. |
| Mud, grass, dust | Cold | Particulate. Comes out mechanically; heat adds nothing. |
| Ink, paint, adhesive | Treat before washing | Temperature is not the variable. Solvent is. |
By fabric
| Fabric | Usual setting | Note |
|---|---|---|
| Cotton, everyday | Cold or warm | Hot shrinks it, especially the first few washes. |
| White cotton, heavily soiled | Hot | The case where hot earns its cost. |
| Synthetics — polyester, nylon | Warm | Hot can set creases into the fibre. |
| Activewear with elastane | Cold | Heat degrades elastic fibre and the garment loses shape. |
| Wool and silk | Cold, gentle | Follow the care label. Heat plus agitation felts wool. |
| Denim and dark colours | Cold, inside out | Slows fading more than any detergent choice will. |
| Bed linen and towels | Warm, hot when needed | Hot for hygiene, warm the rest of the time. |
Love Paks are pre-measured laundry detergent paks made by Love Brands. They work in warm or cold water, in standard and high-efficiency machines. More on washing in cold water.
Sources
- US Department of Energy, Energy Saver — the share of a wash cycle's energy that goes to heating water, and the saving from switching a load from hot to warm or cold.
- ENERGY STAR — clothes washer specifications and water-heating energy use.
- Care-label conventions follow the ASTM D5489 symbol standard used on US garment labels.
Temperature bands vary between machines. Where a garment's care label disagrees with this chart, follow the label.
