When Should You Avoid Using Fabric Conditioner?

Fabric conditioner is a many-splendored thing. "Fabric conditioners (or softeners) come in a variety of different forms, including liquids, dryer sheets, and even beads," says Brian Sansoni of the American Cleaning Institute. "When added to the wash, this laundry product creates a thin, protective layer over each fiber, keeping fabrics soft and smelling great."

However, when used incorrectly, this laundry staple can wreak havoc on certain items. "Fabric conditioner coats the fabric to smooth down the fibers and make it feel softer, while leaving behind a conditioning agent that you can feel when you touch it," explains Patric Richardson of the Laundry Evangelist. "Unfortunately, some fabrics, including microfiber and terry cloth, can be damaged when they are coated." Curious about what other materials you should never ever wash or dry with a fabric conditioner? From delicate cashmere wools to moisture-wicking workout clothes and more, Richardson, Sansoni, and lifestyle expert Cheryl Nelson of Prepare with Cher share their insight.

Related: Simple Solutions to Your Most Frustrating Laundry Problems

person doing laundry
person doing laundry

Getty / Werayuth Tessrimuang / EyeEm

Wools and Delicate Natural Fabrics

If you're using fabric softener when washing or drying your delicate wools, Richardson says you're doing it wrong. "The loft in fabrics, such as wool, cashmere, and mohair, are what give them their lightness and fluffiness, but when you coat them with conditioner, they lose their texture and their warmth," he explains. "Instead of conditioning, wash with soap that will rinse out completely to let their natural feel come through."

Down-Filled Coats and Comforters

Since fabric softener creates a waxy film that's designed to soften your laundry, Richardson says it's not safe to use on down or feather-filled items, like blankets, jackets, and coats. "Down and feather garments rely on the tiny air spaces between the feathers, and using a conditioner coats the feathers and flattens them out," he says. "The best thing to do is treat them like wool and wash with something that will rinse clean."

Swimwear

Typically composed of stretchy synthetic materials, such as polyurethane, swimwear should never be washed with fabric softener, says Nelson. "Swimsuits made of fabrics like spandex, Lycra, elastane, nylon, and polyester don't absorb very much water and therefore dry quickly," she explains. "Washing or drying swimwear with fabric conditioner can cause them to attract more moisture, which can slow down the drying process and leave them with a musty smell and in some cases, lead to mold growth."

Performance Fabrics

While it may be tempting to wash or dry smelly workout clothes with fabric softener, don't—if they're composed of moisture-wicking performance fabric, our experts say it may do more harm than good. "The coating that fabric conditioner leaves behind can harm the ability for these fabrics to wick," Richardson explains. "A better option is to use an enzyme detergent or a color-safe bleach to pull out any oils so they can be as soft as possible without compromising the wicking properties."

Linen

Part of the appeal of linen bedding and clothing is its loose, airy weave, which Richardson says can be compromised by fabric softener. "The little spaces between the threads are what give linen its breathable feel, and the coating from fabric conditioner fills in those tiny air holes," he explains. "A better choice is to toss it in the dryer for five minutes to soften."

Baby Clothes

Of all the laundry items you should never ever use fabric conditioner on, the most important to remember is baby and children's clothes. "The waxy buildup from fabric softener can cause baby clothes (and other children's items labeled as flame-resistant) to become less flame-retardant, and thus more flammable," Nelson explains.