Finding the right pillow for your decorative cover can be surprisingly tricky. You have a beautiful 18×18 inch pillow cover, but what size pillow form should you actually put inside it? The answer isn’t always as simple as it seems. Getting the fit right is crucial for a plump, professional look that lasts. This guide will walk you through everything you need to know to make the perfect choice.
What Size Pillow For 18×18 Cover
For an 18×18 inch pillow cover, you should typically use a 20×20 inch pillow insert. This one-size-up rule is the golden standard in home decor and upholstery. It ensures your cover is fully filled out, creating a luxuriously plump appearance without any saggy corners. Using an insert that’s 2 inches larger than the cover is the key to that coveted, high-end look.
Why not use an 18×18 insert? An insert that matches the cover’s exact dimensions will often look flat and under-stuffed once it’s inside. Fabric takes up space, and seams create tension. The slightly larger insert pushes against the cover, creating tension that results in crisp edges and a full, inviting shape. It eliminates that sloppy, half-empty look that can ruin the aesthetic of a room.
Why the 2-Inch Larger Insert Rule Works
This isn’t just a random tip; it’s based on how fabric and filling behave. Here’s the breakdown:
- Fabric Consumption: The seam allowances on your cover use up fabric, effectively making the interior space slightly smaller than the stated finished size.
- Filling Compression: Most pillow inserts (like down or polyfill) are designed to compress. Starting with a larger size accounts for this compression when you stuff it into the cover.
- Structural Integrity: The gentle pressure from the larger insert keeps the cover taut, preventing wrinkles and ensuring the pillow holds its shape beautifully over time.
Exceptions to the Standard Rule
While the 20×20 insert is the go-to, there are a few situations where you might consider a different size.
- Very Thick or Stiff Fabric: If your cover is made from a heavy material like velvet, wool, or a thick tapestry, the fabric itself has less give. In this case, a 19×19 insert might provide a snug fit without being impossible to close.
- Desired “Squishy” Look: For a more relaxed, casual, and sink-in feel, you might prefer an 18×18 insert. It will be softer and less structured.
- Envelope Closure Covers: Covers with a simple envelope closure (no zipper) can sometimes be harder to stuff with a much larger insert. You might find a 19×19 easier to manage while still getting a good fill.
Types of Pillow Inserts and Their Impact
The material of your insert dramatically affects the final look and feel, even when using the correct size.
Down and Feather Blends
These are the top choice for a luxury, plump look. They compress easily to fit into a smaller cover and then expand to fill every corner. For an 18×18 cover, a 20×20 down insert is ideal. Remember to fluff it vigorously before inserting!
Polyester Fiberfill (Polyfill)
This is a great, affordable, and hypoallergenic option. Polyfill inserts are usually less compressible than down. A 20×20 polyfill insert will work, but it might feel firmer. Don’t be tempted to go to a 21×21, as it could make the cover seams strain.
Foam Inserts
Solid foam inserts are very firm and have almost no give. You should never use a foam insert larger than the cover. For an 18×18 cover, you would need an 18×18 foam insert, or even an 17.5×17.5, to get it to fit without distorting the fabric.
Step-by-Step Guide to Inserting Your Pillow
Getting that perfect, smooth finish requires a good technique. Follow these steps:
- Fluff the Insert: First, vigorously shake, punch, and fluff your pillow insert. This loosens the filling and gets it ready to expand.
- Turn the Cover Inside Out: This might sound counterintuitive, but it helps. Reach into the cover and grab the inner corner opposite the closure.
- Grab the Insert: With your other hand, grab the corresponding corner of the pillow insert.
- Pull the Cover Over: Use the cover corner to pull the fabric over the insert, almost like putting on a sock. This method prevents the filling from getting caught and distributes it evenly.
- Adjust and Close: Once the insert is fully inside, shake the pillow and poke the corners out firmly. Then secure the zipper, button, or envelope closure.
- Final Fluff: Give the finished pillow a final shake and plump to settle the insert perfectly into all four corners.
Common Problems and How to Fix Them
Even with the right size, things can sometimes go a bit wrong. Here’s quick troubleshooting advice.
Pillow Looks Lumpy or Uneven
This usually means the insert wasn’t fluffed enough before inserting, or the filling has shifted. Take the insert out, fluff it again, and redistribute the filling by hand before trying again. Sometimes giving the finished pillow a good few hits helps too.
Corners Won’t Fill Out
This is a classic sign of an insert that’s too small. If you’re using an 18×18, you need to upgrade to a 20×20. If you already are using a 20×20, make sure you are physically pushing the filling into the corners during the final adjustment step.
Cover Seams Are Straining
The insert is too large or too firm for this particular cover. Try a smaller insert (like a 19×19) or switch to a more compressible insert material, like a down alternative.
Closure Won’t Close Easily
Don’t force it! This is a clear sign of an overstuffed situation. Remove the insert and check its true dimensions—sometimes they can vary. You may need to temporarily compress the insert more by rolling it or kneeling on it before quickly closing the cover.
Care and Maintenance for Longevity
To keep your pillows looking their best, proper care is essential. Always check the care labels on both your cover and insert. Most decorative covers are machine washable on a gentle cycle. It’s best to air dry them to prevent shrinking. For pillow inserts, spot cleaning is often safer. Down and feather inserts can usually be professionally cleaned. Polyfill inserts can sometimes be machine washed and dried on low with tennis balls to re-fluff, but this can shorten there lifespan.
If your insert starts to look flat over time, don’t hesitate to replace it. A worn-out insert will make even the most beautiful cover look tired. Having a spare insert on hand makes refreshing your decor quick and easy.
Buying Guide: What to Look For
When shopping for a 20×20 insert for your 18×18 cover, keep these features in mind:
- Material: Decide between down, feather blend, polyfill, or down alternative based on your budget, desired firmness, and allergy needs.
- Construction: Look for inserts with baffle box construction. This means the filling is sewn into separate compartments, which prevents shifting and lumping.
- Weight: Inserts are often sold by fill weight (e.g., 24 oz). A higher weight generally means a denser, firmer pillow.
- Return Policy: Especially when buying online, check if you can return the insert if the size or feel isn’t quite right for your specific cover.
Creative Ideas and Styling Tips
Once you’ve mastered the fit, you can play with style. Mixing different textures and patterns with your 18×18 covers can add depth to a room. Try using a velvet cover with a linen one, or a bold pattern with a solid color. Remember, the plumpness from the correct insert size makes any fabric look more expensive and intentional.
Don’t be afraid to layer pillows. Place your perfectly filled 18×18 square pillows in front of larger lumbar or rectangular pillows. The variation in size and shape creates a dynamic, inviting look on a sofa or bed. The key is that each pillow looks full and well-dressed, thanks to the right insert hiding inside.
FAQ Section
Can I use an 18×18 pillow in an 18×18 cover?
You can, but it likely won’t look its best. An 18×18 insert will often appear under-stuffed and a bit flat once inside the cover due to fabric taken up by seams. For a full, plump look, sizing up is strongly recommended.
What is the best pillow insert for an 18 inch pillow cover?
The best insert is typically a 20×20 inch insert. The best material depends on your preference: down or feather blends for luxury and softness, or a high-density polyfill for a firmer, more affordable, and hypoallergenic option.
How much bigger should a pillow insert be?
The standard rule is to choose a pillow insert that is 2 inches larger than the cover in both dimensions. So for an 18×18 cover, use a 20×20 insert. For a 22×22 cover, use a 24×24 insert, and so on.
My cover has a zip, does that change the insert size?
A zipper closure actually makes it easier to use the correctly sized-up insert (like the 20×20 for an 18×18). It allows you to open the cover fully for easier insertion. The rule remains the same.
What if I can’t find a 20×20 insert?
A 21×21 insert will likely be too large and cause strain. A 19×19 insert is a better alternative if 20×20 is unavailable. It will still provide a fuller look than an 18×18 insert, though it might not be quite as plump.
Choosing the right pillow size for your 18×18 cover is a simple trick that makes a huge difference. By following the one-size-up rule and selecting the appropriate insert material, you can transform your decorative pillows from looking flat and forgettable to plump and professional. It’s a small detail in your home decor process, but it’s one that has an outsized impact on the overall feel of your space. With this knowledge, you can confidently shop for inserts and style your pillows knowing they will look exactly as you envisioned.