Throw Pillow Covers: Sizes, Insert Fit, Closures and Care

Throw pillow covers are removable fabric cases that slip over a pillow insert. The most common sizes are 16, 18 and 20 inches square. Zipper closures give a snug fit, and the fabric’s care label tells you how to wash it.

This article is part of our home decor accessories guide, where you can compare related options.

A cover is the cheapest way to change a sofa or bed. You can swap colors with the seasons without buying new pillows, and you can wash a cover instead of the whole pillow. But the size and closure you pick affect how the pillow looks, and a cover that’s wrong for the insert ends up droopy or lumpy.

A throw pillow cover is a decorative case, usually made of cotton, linen, velvet or a blend, with a zipper or an envelope back. This guide explains sizing and insert fit, the closure types, fabric choices, care and how to style covers.

What sizes do throw pillow covers come in?

Most come in square sizes. One source says common dimensions are 16 by 16, 18 by 18 and 20 by 20 inches, and you’ll also see 22, 24 and 26 inch squares, rectangular lumbar covers and round styles. Listings often show 18 by 18 inches as the default. A lumbar cover is longer than it is tall and suits the middle of a sofa or the front of a bed.

Match the size to the furniture. Small covers look lost on a large sofa, and big covers can take over a small chair. A mix of two or three sizes usually looks balanced. Our decorative pillows guide covers sizes and layering in more detail.

How big should the insert be?

The answer depends on the look you want. One guide says a cover the same size as the insert gives a snug fit, while a cover one to two inches smaller than the insert gives a plumper look. Another suggests a 22 inch insert for a 20 inch cover to get a plump appearance. A third recommends an insert one to four inches larger than the cover.

Because the advice varies, use it as a range. If you like a firm, full pillow, go a couple of inches bigger. If you want a soft, relaxed pillow, use the same size. Measure the cover seam to seam, not the label alone, because stretch and stitching change the real size.

Zipper or envelope closure?

Zippers hold the insert tightly and make the cover easy to remove for washing. One guide says covers with zipper closures provide a snug fit and are easy to remove, while envelope-style covers may fit more loosely. A listing notes that hidden zippers avoid scratching skin or catching hair and stay protected during machine washing. An envelope closure uses overlapping fabric panels at the back, so there’s no hardware at all, and it conceals the opening.

Choose a hidden zipper for a tailored look and an envelope back if you want a simple, flat cover. Check that the zipper runs smoothly, and that the stitching at the corners is strong. See the pillow sham guide for closure notes on bed pillows.

Which fabric should I pick?

Cotton is soft and easy to wash. Linen has a relaxed texture, as our linen bedding guide explains. Velvet looks rich but can show marks. Chenille and boucle add texture. Outdoor covers use weather-resistant fabrics, though you should check the label. Printed covers may be thinner than woven ones, so check reviews for color fading.

Think about use. A sofa cover sees daily wear, so choose a tight weave. A decorative cover on a guest bed can be more delicate. If you have pets or kids, pick a fabric you can machine wash.

How do I wash throw pillow covers?

Check the care label first, because whether a cover can go in the machine depends on the fabric. One listing recommends hand washing or a gentle machine cycle and says not to iron the cover. Another suggests washing the cover inside out. Close zippers before washing to protect the fabric, and use a mild detergent. Air dry or tumble dry low if the label allows, and remove while slightly damp to cut down on wrinkles.

Washing can shrink some covers, especially natural fibers. If a cover shrinks, it may not fit the insert anymore. For delicate fabrics like velvet or embroidery, spot clean or follow the maker’s directions.

How do I style throw pillow covers?

Start with a color plan. Pick two or three colors that match your sofa and rug, and add a pattern in one of them. Mix textures, such as a smooth cotton cover next to a chunky knit. Use odd numbers: three or five pillows look natural, and pairs look formal. Place larger pillows at the back and smaller ones in front.

Swap covers with the seasons. Light linen suits summer, and velvet or wool suits winter. Our floor pillows guide shows how to use big pillows on the floor, and the green sofa guide has color ideas.

How do I mix patterns and colors?

Start with a calm base. Choose one solid pillow cover in a color that matches your sofa or bed, then add one pattern and one texture. A stripe and a floral can sit together if they share a color. Vary the scale: pair a large pattern with a small one. If you feel unsure, stay with two or three colors and let the textures do the work, a guideline that design writers repeat often.

Seasonal swaps are easy because covers are cheap and flat to store. Linen and light cotton feel right in warm months, and velvet or knit feel right in cold ones. Keep a small set of neutral covers on hand so that you can refresh a room quickly.

What mistakes should I avoid?

The most common one is buying the cover without checking the insert. A cover that’s far too big looks limp, and one that’s too small will not close. Another is ignoring the care label, which leads to shrinking or fading. A third is picking too many different sizes in one spot, which makes a sofa look cluttered.

Also check the quality of the zipper and seams before you buy a set. A cheap zipper can snag, and weak seams split when you fluff the pillow. Reading reviews that mention washing results helps you avoid disappointment.

Frequently Asked Questions

What size are most throw pillow covers?

Most are 16, 18 or 20 inches square. Larger squares and lumbar shapes are also common.

Should the insert be bigger than the cover?

A same-size insert gives a snug look, and a one to four inch larger insert gives a fuller one.

Are zipper covers better than envelope covers?

Zippers fit more snugly. Envelope backs are simple and have no hardware.

Can I machine wash throw pillow covers?

It depends on the fabric. Check the label.

Do I have to iron them?

Not always. One listing says not to iron the cover.

Conclusion

Throw pillow covers are an easy way to refresh a room. Pick a common size, choose an insert size for the fullness you like, select a zipper or envelope closure and follow the care label.

Because advice on insert size varies, test one pillow before you buy a whole set. A well-fitted cover keeps its shape and looks good for years.

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