A fitted sheet is sewn by creating four corner pockets that hold the mattress

A fitted sheet starts as a flat rectangle of fabric. You sew elastic into channels at the four corners, which makes those corners cup and grip the mattress. The rest of the sheet stays flat. The elastic does the work — without it, you just have a flat sheet with four holes cut into the corners.

The basic method is: cut the corners, fold and sew the edges to make channels, thread elastic through those channels, and stitch the elastic ends closed. The whole project takes three to four hours for a beginner, mostly because the corners require precision. You will need a sewing machine, elastic (usually 1/4-inch wide), thread, scissors, a measuring tape, and pins.

Key Takeaways

  • Cut 8-inch squares from each corner of your fabric rectangle before you sew anything, because the corners need to be removed to create the pocket shape.
  • Fold the raw edges inward twice and sew them down to create a channel that will hold the elastic.
  • Thread 1/4-inch elastic through each corner channel, pull it tight enough to cup the corner, and sew the elastic ends to the fabric so they do not slip out.
  • Test the fit on your mattress before you finish — if the corners are too loose or too tight, you can adjust the elastic tension before the final stitch.

Measure your mattress and cut the fabric to size

Start with a piece of fabric that is roughly 4 inches longer and 4 inches wider than your mattress. For a standard queen mattress (60 inches by 80 inches), cut your fabric to 64 inches by 84 inches. This extra fabric becomes the elastic channels at the corners.

Lay the fabric flat on a large work surface — a bed, a cutting table, or the floor. Measure 8 inches in from each corner along both edges and mark those points with a pen or chalk. These marks show where you will cut the corner squares out.

Cut the corners and fold the edges

Cut an 8-inch square from each corner. You are removing the corner entirely, not just notching it. After you cut, you will have a cross-shaped piece of fabric with four flaps hanging down from the sides.

Fold one raw edge inward 1/2 inch and press it flat with an iron. Fold it inward again another 1/2 inch and press. This double fold hides the raw edge and creates a finished edge. Do this on all four sides of the sheet, including the flaps that will become the corner pockets.

Sew the folded edge down with a straight stitch, staying close to the inner fold. Use a thread color that matches your fabric. Sew all the way around the perimeter, including down both sides of each corner flap.

Create the elastic channels at each corner

At each corner, you now have two fabric flaps that hang down from the sides of the sheet. Fold these two flaps together so they overlap, creating a pocket. Pin them in place. The pocket should be roughly 3 inches deep — deep enough to hold elastic and the mattress corner.

Sew along the sides of each pocket to close them, leaving the opening at the top (the opening faces toward the center of the sheet). Sew from the edge of the sheet down about 3 inches. This creates a closed pocket with an opening at the top where you will insert the elastic.

Measure the opening at the top of each pocket. This is where the elastic will go. Most corner pockets are 4 to 5 inches wide at the opening.

Thread and find the elastic

Cut four pieces of 1/4-inch elastic, each about 12 to 14 inches long. Attach a safety pin to one end of the first piece of elastic. Use the safety pin to thread the elastic through the opening of the first corner pocket, pushing it all the way through so it comes out the other side.

Pull the elastic tight — not so tight that the corner bunches, but tight enough that when you place the sheet on the mattress, the corner cups and grips. A good test is to hold the corner pocket in your hand and pull the elastic until the pocket forms a cup shape that looks right for your mattress depth. Mark where the elastic ends meet with a pin.

Fold the elastic ends back into the pocket opening and sew them down to the fabric with a short, strong stitch. Sew back and forth over the elastic ends several times so they cannot slip out. Repeat this process for all four corners.

Test the fit and finish the sheet

Place the sheet on your mattress and check how it fits. The corners should cup snugly without pulling the sides of the sheet too tight. If a corner is too loose, you can open the pocket again, pull the elastic tighter, and re-sew the ends. If a corner is too tight, loosen the elastic slightly and re-sew.

Once the fit is right, trim any loose threads and give the entire sheet a final press with an iron. The fitted sheet is now ready to use.

Common mistakes to avoid

The most common error is cutting corners that are too small. If your corner squares are smaller than 8 inches, the pockets will not be deep enough to hold the elastic and grip the mattress properly. Measure twice before you cut.

Another frequent mistake is sewing the elastic too tight. This pulls the sides of the sheet inward and makes it impossible to fit the sheet smoothly over the mattress. Elastic should be snug, not strained. You should be able to stretch the corner pocket by hand without the elastic feeling like it is about to break.

Some sewers forget to double-fold the raw edges before sewing. This leaves raw fabric exposed, which will fray in the wash. Always fold twice and press before you sew.

Frequently Asked Questions

What size elastic should I use for a fitted sheet?

Use 1/4-inch wide elastic, which is the standard size for fitted sheets. It is narrow enough to fit through the corner pocket opening without bunching, but wide enough to hold securely without rolling or twisting. You can find it at any fabric store.

Can I make a fitted sheet without cutting corners?

No. The corners must be cut out and removed to create the pocket shape. Without cutting, you cannot fold the fabric into a cup that grips the mattress. The cut corners are what make a fitted sheet work.

How tight should the elastic be?

Tight enough that the corner pocket cups and holds the mattress corner, but loose enough that you can stretch the pocket by hand without strain. If you have to pull hard to fit the sheet on the mattress, the elastic is too tight. If the corners slip off easily, it is too loose.

What fabric works best for a fitted sheet?

Cotton or cotton-blend fabric is easiest to work with because it does not slip under the needle and presses flat with an iron. Avoid stretchy fabrics like jersey knit unless you have experience sewing with them — they require different techniques and are harder to control.

Do I need a serger to make a fitted sheet?

No. A regular sewing machine is all you need. A serger can finish the edges more neatly, but a straight stitch with a double-folded edge is durable and looks professional on a fitted sheet.