What ruffles are and why the method matters
A ruffle is a strip of fabric gathered or pleated so it bunches up and creates a decorative, wavy edge. You see them on pillowcases, sleeve cuffs, aprons, and dress hems. The three main ways to make them—gathering with thread, using elastic, or knife pleating—produce different looks and work better on different fabrics. Lightweight cotton gathers smoothly; heavier fabrics like denim need elastic or pleats to avoid bulk.
The choice matters because gathered ruffles on thick fabric can create lumps where you attach them, while elastic ruffles on delicate fabric can pucker. This guide walks you through each method so you can pick the one that fits what you are making.
Key Takeaways
- Gathered ruffles use two parallel rows of long stitches pulled tight to bunch the fabric, and work best on lightweight cotton and linen.
- Elastic ruffles use a strip of elastic sewn into a casing, creating even gathers that hold their shape through washing, and suit heavier fabrics.
- Knife pleats are sharp, folded creases pressed flat and stitched down, and create a formal look that requires more fabric and pressing time.
- The width of your ruffle strip and the length of the finished edge determine how much fabric you need—a ruffle twice the finished length will gather moderately full.
- Attach ruffles to a garment edge using a seam allowance of ¼ to ½ inch, with the ruffle sandwiched between two fabric layers so stitches do not show on the front.
Gathered ruffles: the most common method
Gathered ruffles start with a long strip of fabric. Cut a strip on the grain (parallel to the selvage) that is twice as long as the edge where you want the ruffle to go. The width depends on how deep you want the ruffle—a 2-inch-wide strip creates a modest ruffle, while 4 inches or more makes a dramatic one. Add ½ inch on each long edge for seam allowance.
Sew two parallel rows of long, loose stitches (length 4 to 5 on most machines) down the length of the strip, one row ¼ inch from the top edge and one row ¼ inch from the bottom edge. Leave long thread tails at both ends—at least 6 inches. Do not backstitch; you need those threads loose so you can pull them.
Hold one thread tail at each end and gently pull both threads at the same time. The fabric will bunch up. Keep pulling until the ruffle strip is the same length as the edge you are attaching it to. Distribute the gathers evenly by sliding fabric along the threads. Knot the thread tails together to lock the gathers in place.
Pin the gathered ruffle to the right side of your garment edge, with the ruffle facing inward (toward the garment). Sew through all layers with a ¼-inch seam allowance. Fold the ruffle outward and press. If you want a finished look, fold the raw edge of the ruffle under ¼ inch and topstitch it down, or bind it with bias tape.
Elastic ruffles: for fabrics that need structure
Elastic ruffles use a casing—a tunnel of fabric—to hold elastic thread. This method works well on heavier fabrics because the elastic distributes the gathers evenly and the casing hides the elastic inside. Cut a strip of fabric 1 to 2 inches wide and as long as you want the finished ruffle to be (not doubled). The finished ruffle will be the width of this strip minus the seam allowances.
Fold the strip in half lengthwise, right sides together, and sew the long edges with a ¼-inch seam. Turn it right side out and press flat so the seam runs down the center back. Now you have a tube. Fold the tube in half widthwise to find the center, and mark it with a pin.
Thread elastic (¼-inch-wide elastic works well) through the tube using a safety pin or bodkin as a needle. Start at one end and push the safety pin through, pulling the elastic behind it. Leave 1 inch of elastic hanging out at each end. Sew across both ends of the tube to trap the elastic inside, then pull the elastic to gather the tube. The ruffle will bunch up. Distribute the gathers evenly and sew across the ends again to lock everything in place.
Attach the elastic ruffle to your garment the same way you would a gathered ruffle: pin it to the right side of the edge, sew with a ¼-inch seam, and fold it outward. The elastic inside keeps the gathers from flattening out in the wash.
Knife pleats: for a tailored, formal look
Knife pleats are sharp, uniform folds pressed flat and stitched down. They create a crisp, structured ruffle that looks more formal than gathers. This method takes more time and fabric because each pleat must be folded and pressed individually.
Cut a strip of fabric three times as long as the finished edge (because each pleat takes up fabric on both sides of the fold). Decide on pleat width—½ inch, ¾ inch, and 1 inch are common. Mark fold lines on the wrong side of the fabric using a ruler and tailor's chalk or a fabric pencil, spacing them evenly at your chosen width.
Fold the fabric along the first line, bringing the fold line to meet the next marked line. Press with a hot iron. Fold the next pleat the same way, always folding in the same direction. Continue until the entire strip is pleated. Sew a line of stitches down the top edge of the pleated strip, ¼ inch from the edge, to hold all the pleats in place. This is called a stitch line or stay stitch.
Attach the pleated ruffle to your garment by pinning it to the right side of the edge with the stitch line aligned with your seam allowance. Sew with a ¼-inch seam, then fold the ruffle outward and press again to set the pleats permanently.
Calculating fabric length and width
The amount of fabric you need depends on the method and how full you want the ruffle. For gathered ruffles, use twice the length of the finished edge as a starting point—this creates moderate fullness. If you want a very full, dramatic ruffle, use 2.5 times the length instead. For elastic ruffles, use the exact finished length because the elastic does the gathering. For knife pleats, use three times the finished length.
Width is a matter of preference. A 2-inch-wide ruffle is subtle; 3 to 4 inches is standard; 5 inches or more is dramatic. Remember to add ½ inch on each long edge for seam allowance when you cut.
If your finished edge is 36 inches long and you want a gathered ruffle that is 3 inches wide, cut a strip that is 72 inches long (36 × 2) and 4 inches wide (3 inches plus ½ inch seam allowance on each side).
Attaching ruffles so seams stay hidden
The cleanest way to attach a ruffle hides the seam on the inside of the garment. Lay your garment flat with the right side up. Pin the ruffle to the right side of the edge, with the ruffle facing inward (toward the center of the garment, not outward). The raw edge of the ruffle should align with the raw edge of the garment.
Sew through both layers with a ¼-inch seam allowance. Then fold a facing (a strip of fabric, usually 1 to 2 inches wide) over the ruffle, right sides together, and sew again. This sandwiches the ruffle between the garment and the facing. Fold the facing to the inside and press. The ruffle now sticks out from the edge, and all raw edges and seams are hidden inside.
If you do not want to use a facing, you can fold the garment edge over the ruffle seam by ½ inch, press, and topstitch from the right side. This creates a visible line of stitching but is faster and uses less fabric.
Common mistakes and how to avoid them
The most common mistake is not making the ruffle long enough. If you use only 1.5 times the finished length instead of 2 times, the ruffle will look skimpy and flat. Test your gathering on a scrap of the same fabric first—pull the threads and see how full it looks before you commit to the real piece.
Another mistake is using thread that is too short when gathering. If your thread tails are only 2 inches long, you will not have enough to pull and the thread may break. Always leave at least 6 inches of thread on each end.
Uneven gathers happen when you pull one thread harder than the other. Pull both threads at the same time and slide the fabric along them to distribute the bunches evenly before you knot them off.
Puckering at the seam occurs when you sew the ruffle to the garment too tightly. Use a ¼-inch seam allowance and do not stretch the fabric as you sew. If the ruffle is very full, you may need to use a walking foot or reduce the presser foot pressure so the layers feed evenly.
Frequently Asked Questions
Can I make ruffles from knit fabric?
Yes, but gathered ruffles work better than knife pleats on knits because pleats do not hold their shape in stretchy fabric. Use a ballpoint needle and stretch the ruffle slightly as you sew so the seam does not break when the garment is worn. Elastic ruffles are ideal for knits because the elastic keeps the gathers stable.
How do I make a double ruffle?
Cut two strips of fabric and gather or pleat each one separately. Attach them to the garment edge one on top of the other, or attach one, then attach the second ruffle on top of the first seam. Stagger the widths—make the top ruffle narrower than the bottom one so both are visible.
What is the difference between a ruffle and a flounce?
A ruffle is a gathered or pleated strip sewn to an edge. A flounce is a shaped piece cut on the bias or with a curved edge so it flares out naturally without gathering. Flounces require a pattern and more skill, while ruffles are made from straight strips.
Do I need to finish the raw edges of the ruffle before attaching it?
Not if you are using a facing or binding—those cover the raw edges. If you are topstitching the ruffle down without a facing, fold the raw edge under ¼ inch and press before you topstitch, or bind it with bias tape for a polished look.
Can I add ruffles to an existing garment?
Yes. Carefully open the seam where you want the ruffle to go using a seam ripper. Attach the ruffle to one layer, then sew the layers back together with the ruffle sandwiched between them. This works best on hems and cuffs where the seam is straight and straightforward to access.