Does Polyester Shrink When Washed or Dried?

If you've ever tossed polyester clothing into the wash without checking labels first, you may have wondered - Does polyester shrink like other fabrics?

Understanding how to properly launder polyester is key to keeping your favorite tees, dresses, and activewear looking their best.

Here's what you need to know about washing and drying polyester without causing it to shrink.

What Makes Polyester Shrink-Resistant

Polyester is a synthetic fabric made from petroleum-derived polymers that are engineered at the molecular level to resist shrinkage. Long polyester polymer chains interlock to provide stability and shape retention.

Unlike natural fibers like cotton and wool, polyester does not readily absorb moisture. This hydrophobic property allows polyester to dry extremely quickly after washing. The drying process does not distort the shape of the fibers the way it does with cotton.

Thanks to its molecular structure and hydrophobic nature, polyester maintains its dimensions very well during laundering. It retains fit and doesn't warp or shrink.

These attributes make polyester a popular choice for clothing like moisture-wicking athletic shirts, wrinkle-free dress pants, and shapewear where quick-drying and shrink-resistance are desirable.

From everyday t-shirts to formal wear, polyester has become a versatile wardrobe staple that can withstand frequent washing. But there are still factors that can influence shrinkage in polyester.

What Impacts Polyester's Shrink Potential

While 100% polyester made from quality fibers resist significant shrinkage, certain variables can increase shrinkage:

Polyester Blends - Many modern polyester fabrics blend polyester with cotton, spandex, wool, and other natural fibers. These blends make the fabric more prone to minor shrinks since natural fibers shrink more when washed. A cotton-polyester tee will have more shrinking potential than one made of 100% polyester.

Lower Quality Polyester - Cheaper grades of polyester made from thin, low-density fibers can be more susceptible to shrinkage versus high-end performance polyester engineered for stability. Higher quality athletic polyester holds its shape better.

Garment Construction - Tightly stitched fabrics with less open space like preshrunk polyester knits will shrink to less than a loose knit of lower quality. How the garment is cut and sewn also impacts shrinkage potential.

Heat and Agitation - Though generally shrink-resistant, exposing polyester to excessively high temperatures and vigorous washing can damage fibers over time, leading to slight shrinkage. Overheated compact fibers.

So while pure high-quality polyester resists shrinkage, cheaper blended fabrics may experience minor shrinkage when subjected to heat and agitation.

Follow These Tips When Washing Polyester

To avoid any risk of shrinkage when laundering your favorite polyester clothing items:

Read the Care Label - Follow all garment washing instructions. Look for keywords like "preshrunk" which indicate the fabric was pre-treated to resist further shrinkage. Adhere to all temperature, drying, and bleach recommendations.

Wash in Cool Water - Use the coolest recommended water setting to prevent fading, bleeding of bright colors, and unnecessary wear. Warm or hot water is only needed for very dirty clothing.

Avoid High Heat Drying - While polyester can withstand higher temperatures, excessively hot dryer settings may damage fibers over time leading to shrinkage. Opt for low or medium heat.

Line Dry When Possible - Hanging garments to air dry is ideal to completely prevent any heat-related shrinkage, especially for lightweight performance wear. Laying flat to dry also works.

Use a Delicate Cycle - Set your washing machine to a gentle or delicate cycle, which minimizes agitation. Soaking helps loosen stains. Extra rinse cycles prevent detergent residue buildup.

Wash Similar Items Together - Separate light and dark polyester fabrics to prevent fading and bleeding of colors. Group items by weight and construction. Turn clothes inside out.

Use a Mesh Wash Bag - Protecting delicate synthetics in a mesh bag provides an extra buffer against friction, preventing pilling and snags. Great for lingerie and workout wear.

By following fabric care instructions, washing in cool water, skipping the dryer, and using gentle cycles, you can keep polyester from shrinking out of size. Take extra care with blended knits and lightweight performance wear.