How Much Bigger Should a Pillowcase Be Than The Pillow?

Updated December 23, 2019

With the huge amount of pillows available to meet the needs of your specific sleep style and preference, it can get frustrating to find the perfect pillow match to existing bed linens you may have. Various sized pillows, especially those that are a custom length, width, and loft can wreak havoc on your matching decor. But with a little foresight you can narrow down your pillow choices by size, or at the very least be prepared in advance.

If you are worried about having a pillowcase that is smaller than your preferred pillow choice or is struggling with a pillowcase that is bigger than your pillow, this is the article for you. Read on to determine how to best determine the size pillowcases you may need for your choice of pillow.

Pillow Sizes

To start, you should have a good idea of what the average measurements of various sized pillows are. If you have wondered about how big a standard pillowcase is that you may purchase in a store, the following may help explain this.

In order to find a good pillowcase fit, short of sewing your own, you want to start with your pillow dimensions and average loft, or height of pillow when sitting on a flat surface. Of course, the loft may vary from pillow to pillow due to the filling used (for example down might loft up but compress easily, whereas memory foam will be denser).

There are always pillows that are more specialized in their size for various needs, but in this article, we are going to concentrate specifically on those pillows that you rest your head upon each night. Namely, the labels you often see when pillow shopping reflect standard, queen, and king sizes.

Even though these sizes may vary slightly from one brand company to the next, they are generally within a few inches of one another in measurement. This way you can find a covering that fits properly without compressing the pillow and changing how it feels or the support it lends.

Pillow Size Pillow Measurements
Standard 20 x 26 inches
Queen 20 x 30 inches
King 20 x 36 inches

Pillowcases Sizing

As mentioned, the measurements of a pillow are not restricted to the length and width of the pillow, but also the loft. The loft is often closely associated with the support the pillow lends to the sleeper. It also can drastically affect how well a pillow fits in a case since a pillow may end up being restricted in how well it supports your head and neck if a pillowcase is too small

Because of this, don’t assume a pillowcase measurement is what is best for your pillow. Even if a pillow looks like it fits well into a case, always compress the pillow to see how well it provides support and comfort. A well-fitting cover is going to allow the pillow to compress, move, and be shaped to your needs. A case that is too small will make the pillow feel firmer or show outside of the end of the case.

Pillowcase Dimensions

How big is a standard pillowcase? Obviously, you want to purchase a pillowcase that is respective in size to the pillow you have. To allow for loft differences, it is best to purchase a case that provides a one to two-inch addition to the length and width of your pillow. Depending on the type of pillowcase, this also assumes you do not count the flap end of the case if there is one. To better understand the pillowcase options you have, read on:


A housewife style case is very popular because they hold your pillow securely using a zipper, button, or envelope style closure. These allow for a fitted, clean fit and you should look for a size that is only slightly larger than your pillow by approximately 1 inch.

Bag Style

Bag style covers are the most commonly found in stores and are what most consumers think of when they are shopping for a pillowcase. The name describes the style well will an open ‘bag’ end you fit the pillow into. Although they do not enclose the pillow completely and the end stays open, it is designed to extend past the end of the pillow for security. The area your pillow sits within should be 1 to 2 inches larger than the pillow with the end flaps extending an extra 3.5-5 inches.

Oxford and Mock Oxford

These styles are popular for more a more decorative look, but may also be used for sleeping. These coverings are designed to provide a snug fit through a back envelope opening. They also extend beyond the edges of your pillow almost like a frame for an extra 2 to 3 inches, Oxford cases have a mitered corner while the mock doesn’t. Look for measurements that are approximately 1 inch larger than your pillow to provide a snug fit that doesn’t restrict its comfort.


Of course, these measurements are only a suggestion to find an average measurement for common pillow sizes. It is not bad to have a pillowcase too big for the pillow, but it’s always better to have a slightly larger case than one that is too small. Getting a decent fit can make all the difference to how it looks as well as how it feels, however, in case you end up with an oversized pillowcase.

Whatever you do, avoid having a case that is too small as you will compromise the overall feel of your pillow. Measure to approximately 1 to 2 inches larger than the pillow to account for loft differences, and if possible, see how well your pillow fits within the case prior to committing to the cover.