What Size Is A Standard Throw Pillow

When you’re shopping for new pillows or just trying to make your sofa look its best, a common question comes up: what size is a standard throw pillow? It seems simple, but the answer can vary depending on where you look. This guide will clear up the confusion and give you the practical details you need to choose the perfect pillows for your home.

You’ll find that most stores and designers refer to a few common dimensions as standard. Knowing these sizes helps you shop for inserts and covers easily. It also lets you mix and match styles with confidence. Let’s look at the typical sizes you’ll encounter most often.

The most common standard throw pillow size is 18 inches by 18 inches. This square shape is a true workhorse in home decor. You can find it in almost any store, and it fits well on most sofas, chairs, and beds.

After the 18×18 inch pillow, the next most standard size is 20 inches by 20 inches. This has become incredibly popular in recent years. It offers a fuller, more substantial look that works great on larger sectionals or as a single statement pillow on a bed.

For a rectangular option, the standard is usually 12 inches by 20 inches. This is often called a lumbar pillow size. It’s perfect for providing lower back support in a chair or for adding a different shape to your sofa’s pillow arrangement.

Other Common Throw Pilloom Sizes

Beyond the main standards, you’ll see several other sizes frequently. These are not quite as universal, but they are still very common in home goods stores.

16″ x 16″: A slightly smaller square that’s good for tighter spaces or for layering in front of larger pillows.
22″ x 22″: A large square that makes a bold decor statement. It can sometimes replace a small cushion on a deep sofa.
14″ x 20″: Another popular lumbar size, a bit wider than the 12×20.
Round Pillows: Often 18 inches or 20 inches in diameter. These add softness and a different form to your layout.

How to Choose the Right Size for Your Space

Picking the right size isn’t just about the pillow itself. You need to think about the furniture it will live on. A huge pillow on a small chair will look awkward, and a tiny pillow on a big sofa will get lost.

Follow these steps to make the best choice:

Measure your furniture. Note the width of your sofa cushions or the seat area of your chair.
Consider scale. A general rule is that a throw pillow should cover about one-third to one-half of the width of the seat cushion it’s placed on.
Think about use. For sitting back and lounging, standard 18″ or 20″ squares are perfect. For pure lower back support while seated, a lumbar size (12×20 or 14×20) is better.
Plan for multiples. If you want a group of pillows, using different sizes (like a 20″ behind an 18″) creates depth and interest.

Pillow Size Guide for Sofas

Standard 3-Seat Sofa: Two to three 20″ pillows, or three 18″ pillows.
Apartment-Size Sofa: Two 18″ pillows, or one 18″ and one lumbar.
Large Sectional: Three to five pillows in a mix of 20″, 18″, and lumbar sizes.
Accent Chair: One 16″ or 18″ pillow, or one lumbar pillow.

Pillow Size Guide for Beds

On a bed, throw pillows (also called decorative shams) are layered in front of your sleeping pillows. The size of your bed dictates what works best.

Twin Bed: Standard squares (18″ or 20″) work, but often two smaller 16″ pillows are used.
Full/Queen Bed: Two to three standard squares, or two European squares (26″ x 26″).
King Bed: Two to three king-sized standard squares (20″ or 22″), often with larger European shams behind them.

The Critical Detail: Insert Size vs. Cover Size

This is one of the most important tips to get a professional look. Your pillow insert should be slightly larger than your pillow cover. This makes the cover look full and plump, without any saggy corners.

A good rule of thumb is to choose an insert that is 2 inches larger than the cover. For example:

For an 18″ x 18″ cover, use a 20″ x 20″ insert.
For a 20″ x 20″ cover, use a 22″ x 22″ insert.
For a 12″ x 20″ lumbar cover, use a 14″ x 22″ insert.

If you can’t find the exact size up, never go smaller. A larger insert can be stuffed into a smaller cover for a very full look. A smaller insert will look sloppy and underfilled inside a cover.

Understanding Pillow Fill and Loft

The “loft” refers to how full and fluffy the pillow is. The fill material determines the loft, and it affects how the pillow looks in its cover.

Down & Feather Blend: Offers a soft, moldable feel that you can fluff up easily. It conforms to your body and gets that classic “sink-in” look.
Polyester Fiberfill: Provides a firmer, more structured shape. It holds its form well and is a good hypoallergenic option.
Memory Foam or Microbead: Used often in lumbar pillows for solid, conforming support. They are less about fluff and more about function.

For a plush look, choose a down blend insert that is 2+ inches larger than your cover. For a more structured, modern look, a fiberfill insert that matches the “larger insert” rule works great.

Mixing and Matching Sizes and Shapes

Creating a stylish pillow arrangement is an art. Using different sizes is the key to a dynamic, inviting look. Here’s a simple formula you can use on a sofa:

Start with the largest pillows in the back. Place two 22″ or 20″ square pillows in each corner.
Layer a medium size, like an 18″ square, in front of each large pillow.
Add a final accent in the front center. This could be a lumbar pillow (12×20), a round pillow, or even a smaller 16″ square in a contrasting texture.

Don’t be afraid to mix shapes too. Squares, lumbars, and rounds together look more collected and interesting than all identical squares. Just keep your color or pattern scheme somewhat cohesive so it doesn’t look to chaotic.

Where Standard Sizes Might Differ

It’s good to know that “standard” can shift a bit depending on context. Some decor styles have there own typical sizes.

Outdoor Pillows: Often come in 17″ x 17″ or 18″ x 18″ as a standard. They might be slightly smaller to fit better on patio furniture.
European Shams: These are larger square pillows for beds. The standard sizes are 26″ x 26″ and 28″ x 28″.
Boudoir Pillows: These are small rectangular bed pillows. A standard size is 12″ x 16″.
Floor Pillows: These are much larger, often starting at 24″ x 24″ and going up to 36″ or more.

Practical Tips for Buying and Maintaining Throw Pillows

Now that you know the sizes, here are some extra tips to help you shop and care for your pillows.

Always check the care label. Many decorative covers are “dry clean only,” but many are also machine washable.
Invest in high-quality inserts. You can change covers seasonally, but a good set of inserts will last for years and improve every cover you put on them.
Fluff your pillows regularly. This maintains their shape and loft, especially if they are down-filled.
When shopping online, always read the dimensions in the product description. Don’t rely just on the name or product photo.

Remember, the goal is to create comfort and style. If a size feels right to you in your space, even if it’s not the most common standard, then it’s the correct choice. Decor rules are more like helpful guidelines.

FAQ Section

What is the most common throw pillow size?
The 18-inch square pillow is the most common and widely available standard size. The 20-inch square is a very close second and has become extremely popular.

What size is a standard pillow for a couch?
For a standard couch, 18-inch or 20-inch square pillows are the typical choice. Most sofas look balanced with two to three pillows of this size.

What size is a normal decorative pillow?
Normal decorative pillow sizes are 18″x18″, 20″x20″, and for lumbar shapes, 12″x20″. These are the sizes you will find the most covers and inserts for.

How many throw pillows on a sofa is normal?
For a typical three-seat sofa, two to three throw pillows is a normal, functional amount. Larger sectionals can handle four to five. The key is to leave enough sitting room so you don’t have to move all the pillows to sit down.

Should all throw pillows be the same size?
No, using a mix of sizes (like 20-inch and 18-inch squares together) creates a more professional and layered look. It adds depth and visual interest to your furniture.

What size pillow goes in an 18×18 cover?
You should use a 20×20 inch insert for an 18×18 inch cover. This ensures the cover is fully filled out and looks plump, not saggy. A smaller insert will not look good.

Choosing the right throw pillow size finally doesn’t have to be complicated. Start with the 18-inch or 20-inch square as your anchor. From there, you can add in other sizes for support and style. With the simple rule of buying an insert slightly larger than your cover, you’ll achieve a polished look every time. Now you can shop with confidence and arrange your pillows like a pro.