What Does Fabric Softener Actually Do?

Laundry day usually involves hampers full of clothes, a heavy container of detergent, and a fabric softener like Downy or Snuggle. While some people consider the latter indispensable, others think that fabric softener makes little difference in the final laundry result and that the Snuggle Bear is nothing more than a furry propagandist. So what does fabric softener actually do?

Fabric softener is intended to keep your laundry soft to the touch, reduce wrinkles, and add a “clean” scent as an olfactory signal you’re no longer dealing with a smelly pile of socks. Fabric softener can also reduce static cling by reducing friction between fibers, which can make clothes last longer. It accomplishes all of this by using lubricating chemicals that act on the fibers. Early softeners used oil, while modern-day brands have synthetic chemicals like polydimethylsiloxane (PDMS) or other silicone derivatives. Think of fabric softener as a kind of moisturizer for your laundry.

So why not use it? Fabric softener can have some downsides. Like laundry detergent, some liquid fabric softeners may contain chemicals that can irritate the skin of sensitive individuals. If you use dryer sheets, the material may clog the dryer filter. Dryer balls are the most convenient type of fabric softener, but they can leave clothes feeling stiff.

Choosing to use fabric softener can also depend on what kind of clothes you’re washing. If you have a lot of athletic wear with moisture-wicking properties, fabric softener may “clog” the fabric, reducing its ability to move moisture away from the skin. It’s also not great for towels, as it has the potential to reduce their absorbency. Nor is it advisable to use fabric softener on polyester, nylon, or infant clothing, which is often made from flame-resistant materials that might be affected by the softener.

If you're on the fence about whether or not you should be using a fabric softener at all, try washing a small load of laundry with a fabric softener and one without to see if you notice—or feel—any difference. If not, you can probably get by without the additive.

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