Fabric softener, dryer sheets and wool dryer balls all promise softer laundry, but they work in different ways and suit different loads. This guide sets out what each one does, where each falls short and which fabrics to be careful with, using independent testing and expert advice rather than marketing claims.
The quick answer
| Fabric softener | Dryer sheets | Wool dryer balls | |
|---|---|---|---|
| Where it goes | Washing machine (final rinse) | Tumble dryer | Tumble dryer |
| How it works | Coats fibres with softening agents | Heat transfers a softening coating onto the load | Tumbles between items to separate and fluff them; adds nothing to the fabric |
| Softness | Noticeable, but can build up over time | Noticeable | Softer and fluffier than no ball, but less silky than a coating |
| Static | Reduces it | Reduces it | Can help a little |
| Scent | Usually scented | Usually scented | Unscented |
| Towels | Which? advises against | Coating can affect absorbency | Fine |
| Single-use or reusable | Used up each wash | Single-use | Reusable |
How fabric softener works
According to Which?, fabric softeners contain emulsifiers that coat fabric in a thin layer that repels water and acts as a lubricant, which is what makes clothes feel soft. They also contain cationic surfactants, positively charged substances that cancel out the static that washing can create.
The catch is build-up. Which? says regular use leaves a waxy coating that builds up wash after wash, so clothes can end up feeling stiff rather than soft, and detergent finds it harder to get into the fibres. It also warns that softener shouldn't be used on anything labelled flame-resistant, which includes many children's items, so always check the care label.
Softener and towels
This is where Which? is clearest: don't use fabric softener on towels. In its guide to fluffy towels, it explains that the coating builds up, eventually leaves towels feeling crispy and stops water penetrating the fibres, so they won't absorb water as well. Its laundry expert adds that the same coating can clog sportswear made to wick away sweat, and can cause problems for waterproof fabrics, swimwear and wool.
How dryer sheets work
Dryer sheets are thin, single-use sheets coated with softening and anti-static agents. As the load tumbles, the dryer's heat transfers that coating onto your laundry, according to Good Housekeeping's comparison of dryer sheets and dryer balls. That gives noticeable softness, less cling and, usually, a scent.
The same source says dryer sheets shouldn't be used on flame-resistant sleepwear, microfibre, fleece and many sports or performance garments, because the coating can reduce flame resistance and leave residue that affects absorbency or wicking.
Dryer sheets and your lint filter
Residue can end up in the machine too. Iowa State University's extension service notes that some fabric softener sheets leave enough residue to make the lint screen cloudy and tacky. If that happens, soak the screen in hot, soapy water and clean it with a bristle brush. Whatever you use, clean the lint filter as your dryer manual tells you.
How wool dryer balls work
Wool dryer balls are firm balls of felted wool that go in the dryer with your wet washing. Good Housekeeping explains that they work through physical motion rather than a chemical coating: they separate garments as they tumble, which fluffs them up. Because they don't deposit anything on the fabric, they won't feel as silky as a sheet or softener.
In Expert Reviews' hands-on test of three types of dryer ball, the wool balls scored best for softness, and towels came out "fluffier and more tactile" than with no ball. The same reviewer describes wool balls as quiet in the drum and gentle on clothing, and notes that they shed a little and don't last forever. They had less effect on creases than a solid plastic ball.
What we don't claim: in that same test, drying time for towels changed very little. Results depend on your dryer and load, so we don't promise faster drying or lower bills.
A note on essential oils
You'll often see advice to add a few drops of essential oil to wool balls for scent. Good Housekeeping's cleaning lab cautions against this, because essential oils are flammable and can build up over time. If you want scented laundry, a scented detergent or softener is the simpler route.
Which one should you use?
- Towels, tea towels and microfibre cloths: skip softener and dryer sheets, as both can reduce absorbency. Wool dryer balls are a good fit here.
- Sportswear and fleece: avoid coatings that can clog the fibres. Follow the care label, as many technical fabrics shouldn't be tumble dried at all.
- Everyday cottons and bedding: any of the three can work. Dryer balls help keep sheets and duvet covers from twisting into a damp clump.
- If you want maximum silkiness, static control or scent: softener or dryer sheets will do more than dryer balls. You can also combine sheets and balls, says Good Housekeeping, but don't expect a dramatic difference.
- Wool jumpers: none of the above. Which? advises against tumble drying woollens and says a dryer ball is unlikely to stop a jumper shrinking. Dry knitwear flat.
Our wool dryer balls
Our XL wool dryer balls in 100% natural New Zealand wool are about 7 cm across and around 40 g each. They're reusable, and every pack of 4, 6 or 8 comes with a cotton storage bag. For how many to use per load and how to look after them, read our guide to using wool dryer balls, or browse the Laundry & Drying collection.
Frequently asked questions
Can wool dryer balls replace fabric softener?
For towels and everyday cottons, many people use them instead. They soften by tumbling between items rather than coating the fibres, so they won't feel quite as silky as softener or dryer sheets. If you want that extra slip or a scent, softener is the stronger option.
Should I use fabric softener on towels?
Which? advises against it. It says softener leaves a coating that builds up and stops water getting into the fibres, so towels absorb less well and can end up feeling crispy.
Do dryer sheets leave residue in the tumble dryer?
They can. Iowa State University's extension service notes that some sheets leave enough residue to make the lint screen cloudy and tacky. Check the filter, and wash it in hot, soapy water with a brush if it's clogged.
Can I use wool dryer balls and dryer sheets together?
Yes. Good Housekeeping says you can combine them, but the usual dryer-sheet rules still apply, and using both won't make clothes dramatically softer.
Can I tumble dry wool jumpers with dryer balls?
We wouldn't. Which? advises against tumble drying woollens at all and says a dryer ball is unlikely to stop a jumper shrinking. Dry knitwear flat.
Sources: Which?: why our laundry expert doesn't use fabric softener · Which?: how to get fluffy towels · Which?: the best way to dry a wool jumper · Expert Reviews: do tumble dryer balls really work? · Good Housekeeping: dryer sheets vs dryer balls · Iowa State University Extension: keeping your clothes dryer safe. Checked 23 October 2026.