How to Measure Pillows for Covers: A Simple Guide for Perfect Fit

If you’ve ever bought a decorative pillow cover only to find it fits awkwardly, you’re not alone. Getting the measurements right is key to that snug, magazine-worthy finish.

Whether you’re making your own covers or shopping online, this guide on how to measure pillows for covers will walk you through everything you need to know, with practical tips and simple tools.

How Do You Measure Pillows for Pillow Covers

You don’t need fancy tools—just a flexible tape measure and your pillow of choice.

Step-by-Step Measuring Guide:

1. Lay the pillow flat on a smooth, hard surface such as a table or clean floor. Be sure to fluff it beforehand to restore its natural shape and ensure accurate fullness.

2. Measure seam to seam (not corner to corner) across the center horizontally using a soft tape measure. Don’t pull the tape too tightly—just enough to touch both seams.

3. Repeat vertically, also seam to seam, to get the full height. Take note if your pillow has piping or edging—measure to the stitching inside, not the decorative trim.

4. Round up to the nearest half inch for a proper fit, especially if using non-stretch fabrics that don’t give easily. A too-tight cover will look awkward and may strain the seams.

Most square decorative pillows will fall into standard sizes like:

• 16 x 16 inches – great for layering on beds and chairs

• 18 x 18 inches – a go-to for living room accents

• 20 x 20 inches – offers plush, lounge-worthy support for sofas and sectionals

Pro Tip:

For a plush, full look, order pillow covers that are 1 inch smaller than the insert. For example, use an 18” cover for a 20” insert. This creates a tight, upscale appearance without wrinkling or drooping fabric.

When I refreshed our living room for the holidays, I accidentally ordered 18” covers for 16” pillows—what a flop! Luckily, I reused them later when I upgraded the inserts. Meanwhile, keeping the whole family cozy was easy thanks to our Puffy Lux Mattress, which always makes the space feel pulled together and extra comfy.

How to Measure Fabric for Pillows

If you’re sewing your own covers, fabric measurements matter even more. A slight miscalculation could mean a cover that doesn’t fit, gaps that don’t close, or awkward bunching that spoils the look.

Fabric Measurement Basics:

• Add 1 inch seam allowance to each side (½ inch on each edge), which allows enough room for stitching while preserving the final pillow size.

• For a snug envelope-style back:

  • Cut one front panel at full size (e.g., 18 x 18 for an 18” pillow) to give the face of the pillow a smooth, tailored look.

  • Cut two back pieces: each half the width of the pillow + 4–5 inches for overlap. This ensures enough material for the back panels to overlap and hold the pillow in place securely.

This gives you room to sew without compromising the fit. If you’re using thicker fabric like velvet or chenille, consider adding an extra ½ inch to the width for easier turning and closing. Always prewash your fabric if it’s cotton or linen to prevent future shrinkage.

Measuring Different Types of Pillows

Not all pillows are shaped the same, so here’s how to approach them:

Square & Rectangular:

• Measure width and height, seam to seam, using a flexible tape measure for accuracy.

• These are the most common and easiest to size, typically found on sofas, beds, and accent chairs.

• For box-style pillows with depth, measure thickness and choose a gusseted cover for a snug fit.

Round:

• Measure across the widest part (diameter) to get the true face size of the pillow.

• Measure the depth as well if you want a boxed edge style that hugs the pillow’s shape.

• Note that round pillows often need covers with drawstrings or zippers along the edge for proper closure.

Bolsters (cylindrical):

• Measure length from end to end, going straight across the central axis.

• Measure diameter from one side to the other for the round ends.

• Consider extra fabric if the cover design includes decorative end caps or piping.

Odd-Shaped:

• Trace outline on paper and measure longest width and height to get a reference for custom covers.

• Add ease for maneuvering if the cover is zippered, especially around curved or angled edges.

• For asymmetrical designs, label the traced outline for orientation when sewing or shopping for covers.

Common Mistakes When Measuring Pillows

• Measuring loosely or over rounded edges, which can result in covers that look sloppy or oversized.

• Skipping seam allowances when making your own, often leading to too-small covers that won’t close or fit properly.

• Ignoring pillow fullness—some inserts are flatter or firmer than others, and their volume will affect how a cover fits and looks when stuffed.

• Guessing instead of measuring—sizes can vary, even within the same brand, and relying on label assumptions can lead to mismatches in fit and shape.

Last spring, I mixed and matched a few new throw pillows for our master bedroom. Using a measuring tape saved me from mismatched covers—and thanks to our Puffy Royal Mattress with its perfectly tailored bedding, everything came together with a designer finish.

Tips for Best Results

• Fluff pillows before measuring to get the most accurate dimensions. A flat pillow can give misleading numbers, especially around corners or edges.

• Use high-quality inserts that maintain their shape. Cheap or worn inserts can sag, causing covers to wrinkle or hang unevenly.

• Check fabric stretch—woven cottons behave differently than velvets or knits. Stretch fabrics may allow for tighter fits, while rigid fabrics require more precise cuts.

• Keep a chart of your pillow sizes for quick future reference. This is especially helpful if you rotate seasonal covers or shop for new ones throughout the year.

• Choose a consistent color palette for a polished look across all bedding. It helps create a cohesive space, whether you’re mixing patterns or layering textures.

Final Thoughts

Understanding how to measure pillows for covers is an easy but essential skill for making any room feel put together.

From accurate sizing to fabric allowances and avoiding common pitfalls, a little prep goes a long way.

Whether you’re decorating for the season or redoing a room, taking the time to measure properly helps every piece look intentional—and feel incredibly comfortable.