Mitered corners are a way to professionally finish 90-degree corners. You’ll often use them when hemming napkins, scarves, tablecloths, placemats, vents, and even wrap skirts and dresses. They’re also frequently used in quilting, both for binding the quilt and for adding a decorative border around the quilt top. In this article, we’ll cover 2 methods that only use the original piece of fabric you’re working with, 1 method that uses bias binding, how to bind the edges of a quilt using mitered corners, and how to add a border around a quilt top.
Mitered corners are best suited for woven fabrics that press and crease well, such as cotton or linen. You can sew mitered corners on all weights of fabric, but the heavier your fabric is, the wider of a border you’ll need to do if you’re following the first two methods.
Contents list:
- Method 1: Mitered Corners with Sewn Corner – very clean finish
- Method 2: Mitered Corners with Folded Corner – a less sharp finish but useful for narrow borders
- Method 3: Mitered Corners with Binding – if you can’t lose any width/length from your fabric
- Quilt Binding with Mitered Corners
- Quilt Top Border with Mitered Corners
Method 1: Mitered Corners with Sewn Corner
Supplies:
- Square or rectangular piece of fabric
- Fabric marking tool of your choice
- Quilting ruler
- Rotary cutter and/or fabric scissors
- Iron
- Point turner
- Sewing machine
- Edge stitching foot (optional)
- Matching thread
- Pins
Method summary:
This method involves sewing a diagonal line that forms the miter at the corner. It creates a really clean finish with relatively little effort, but it can be fiddly to sew if you’re working on a project that calls for a really narrow border so it’s best suited for wider borders.
Uses:
Curtains, placemats, hems on garments like wrap dresses and wrap skirts, vents, and splits.
Step-by-step instructions:
Step 1: Start by drawing some guidelines. Decide on how wide you would like your border to be. I went with 1” (2.5 cm) wide borders for this tutorial, but you can make them as narrow or as wide as you like. Draw two parallel lines from the cut edge of your fabric, in the width you chose. Repeat this step on all the edges that meet in the corner you would like to miter.
Step 2: Fold the fabric along the first line, and press. Then, fold again at the second line, and press. Repeat on all the sides you marked in Step 1.
Step 3: Unfold the edges you just pressed so that only one fold remains in place.
Step 4: Using a quilting ruler, align the 45-degree angle with the folded-in edge of the fabric, and slide the ruler until its edge is touching the bottom corner of the diamond shape that is formed at the corner of the fabric. Mark this line.
Step 5: Press the corner in, using the 45-degree angle line you just marked in Step 4.
Step 6: Unfold the corner, and fold the fabric diagonally with the right sides touching until the two edges are on top of each other. Pin into place.
Step 7: Sew a straight line using a straight stitch with a length of 2.0 – 2.5 following the line you drew in Step 4. Backstitch at the beginning and the end.
Step 8: Trim the triangular excess of fabric so that there is ⅛” – ¼” (3 – 6 mm) of fabric left from the line of stitching.
Step 9: Turn the corner right side out. You can use a point-turner to make sure the corner is neat and sharp. You can also press the mitered corner so it lays nice and flat.
Step 10: Using an edge stitching foot, topstitch the border along its folded edge. When you reach the corner, stop with your needle down. Raise the presser foot, pivot the fabric 90 degrees, lower the presser foot, and continue sewing. You can use a stitch length of 3.0 – 3.5 for this step.
Tips:
Once you wrap your head around the mechanics of a mitered corner, you can start changing certain elements like making the first fold narrower than the width of your border to reduce bulk, or playing with different widths of borders. Try a narrower border on napkins or scarves, and a wider border for curtains or hems.
Method 2: Mitered Corners with Folded Corner
Supplies:
- Square or rectangular piece of fabric
- Fabric marking tool of your choice
- Quilting ruler
- Rotary cutter and/or fabric scissors
- Iron
- Sewing machine
- Edge stitching foot (optional)
- Matching thread
- Pins
Method summary:
This method involves folding the fabric in a way that creates a mitered corner and topstitching it into place. Unlike the first method, there aren’t any stitches securing the two sides of the miter together, so it’s less secure. The tip of the corner also usually doesn’t turn out as sharp as the corners that come out of Method 1. Despite its shortcomings, it’s a simple technique that comes in handy for really narrow borders where it would be difficult to execute the first method.
Uses:
Napkins, scarves, tablecloths, or any other project that requires a narrow hem/border.
Step-by-step instructions:
Step 1: Start by drawing some guidelines. Decide on how wide you want your border to be. I went with 1” (2.5 cm) wide borders for this tutorial, but you can make them as narrow or wide as you like. Draw two parallel lines from the cut edge of your fabric, in the width you chose. Repeat this step on all the corners that you would like to miter.
Step 2: Turn the fabric 45 degrees so that the corner you would like to miter is at the top. Identify the two points where the first and second lines you marked intersect, and draw a line that passes through both of them.
Step 3: Cut the corner off following the diagonal line you marked in Step 2.
Step 4: Draw another guideline, parallel to the one you drew in Step 2, touching the point where the second lines from Step 1 intersect. Another way to make sure this guideline is in the correct spot is to measure the width from the diagonally cut edge to the new guideline. It should be half the width of the border width you decided on, so ½” (1.25 cm) in my case.
Step 5: You will now press along all the guidelines you marked to create some guiding creases. First, fold the fabric along the first line you drew in Step 1 and press. Next, fold the fabric again, this time on the second line, and press. Repeat on the other edge(s). Finally, unfold the edges you just pressed, and fold the diagonally cut corner following the guideline you drew in Step 4. Press with your iron.
Step 6: With the corner still folded in, fold the sides back in using the creases you formed in Step 5. Repeat on the other edge(s). You should see the miter forming on the corner.
Step 7: Pin or clip your folded fabric so that the mitered corner stays secure before you stitch it
Step 8: Using an edge stitching foot, topstitch about ⅛” (2-3 mm) from the folded edge. When you reach the corner, stop with your needle down. Raise the presser foot, pivot the fabric 90 degrees, lower the presser foot, and continue sewing. You can use a stitch length of 3.0 – 3.5 for this step.
Method 3: Mitered Corners with Bias Binding
Supplies:
- Square or rectangular piece of fabric
- Double-fold bias binding (home-made or store-bought)
- Fabric marking tool of your choice
- Sewing machine
- Matching thread
- Pins
Method summary:
If you don’t want to fold the edges of your fabric to form the mitered corner and border, you can use bias binding. It takes a bit longer to do than the previous methods, requires additional material, and catching the back of the binding can be fiddly. But you won’t lose any width or length from your fabric, and you’ll get to add a fun pop of color or pattern with the bias binding of your choice. In this tutorial, I’ll demonstrate how to do this technique using ½” (12 mm) wide double-fold bias tape, but you can use any width you like once you get the hang of it.
Uses:
Tablecloths, napkins, placemats, quilts.
Step-by-step instructions:
Step 1: Put a pin ¼” (6 mm) in from the corner of the fabric where you would like to form the miter. If you’re using a different width of bias tape, place the pin in by the width of the first crease of the bias tape.
Step 2: Open up your bias tape, and place it right sides facing with your fabric. Make sure the raw edges of the fabric and the bias tape are aligned. You can pin it into place, or just guide it with your hand as you sew.
Step 3: Start sewing on the crease of the bias tape, which is approximately ¼” (6 mm) in. Use a straight stitch with a length of 2.5 mm. When you reach the pin you placed in Step 1, stop and backstitch. Remove the pin.
Step 4: You will now fold the bias tape in a way that leaves enough fabric at the corner to form the miter. First, fold the free end of the bias tape up, wrong sides of the bias tape facing each other. Next, fold it back down so that the right side of the bias tape is against the right side of the fabric, and the raw edges of the two are once again aligned. Check to make sure the corner is nice and square with no accidental folds or bumps. Pin into place.
Step 5: Make a marking ¼” (6 mm) down from the corner, on the crease of the bias tape.
Step 6: Start sewing exactly on the marking you just made, backstitching at the beginning. Continue sewing down the crease of the bias tape, and repeat Steps 3 – 6 for each corner you want to miter. Precision is important here. You can check your work by looking at the wrong side of your fabric and seeing if the two lines of stitching meet at the corner without extending past the corner.
Step 7: Gently fold the bias tape over the corner to reveal the mitered corner. On the back, fold one side of the bias tape so that it covers the stitching line, and then fold the other side on top of it. You’ll see that they form another mitered corner. Pin into place.
Step 8: Now it’s time to secure the back of the bias tape into place. You have two options here: you can either use your sewing machine to topstitch it into place, or you can hand sew it for a cleaner look on both sides.
Quilt Binding with Mitered Corners
Supplies:
- Your finished quilt with exposed edges, trimmed and ready to be bound
- Fabric for the binding
- Quilting ruler
- Rotary cutter and/or fabric scissors
- Sewing machine
- Matching thread
- Pins
Method summary:
A classic place to use mitered corners is in the binding of a quilt. It produces really neat looking corners on both sides of your quilt and it’s easy to do. This method is almost identical to the third method we went over featuring bias binding with mitered corners, but I’ll show you a couple of different tricks for an extra neat finish.
Uses:
Binding the edges of a finished and trimmed quilt.
Step-by-step instructions:
Step 1: Start by preparing your binding strips. Here I’m using 2.5” (6.3 cm) wide strips of contrasting fabric. For this tutorial, I’m working with a small sample, but if you’re working on a larger quilt you will likely need to piece together a few strips of binding. When you’re done, press your binding in half width-wise, wrong sides touching.
Step 2: Start sewing the binding to the quilt using a straight stitch and a ¼” (6 mm) seam allowance. Stop with your needle down when you are ¼” (6 mm) away from the corner. Lift your presser foot, and pivot the quilt 45 degrees. Lower the presser foot back down, and sew off to the corner of your quilt in a diagonal line.
Step 3: Fold the binding up along the diagonal line you have just sewn, and then fold it back down so that the raw edges of the binding are aligned with the raw edge of your quilt. Pin or clip into place to secure the fold.
Step 4: Start sewing again with a ¼” (6 mm) seam allowance, going down the other side of your quilt. Backstitch at the beginning. Repeat Steps 2 – 4 on the three remaining corners of your quilt.
Step 5: Fold your binding up and over the raw edge of your quilt. Using a hand sewing needle and some thread that matches the color of your binding, sew the back of the binding into the backing of your quilt. Here you can use a felling stitch or a whip stitch for a clean look to the back. When you reach a corner, continue sewing the binding down to the end of the corner. Then, fold the other side of the binding over the first side, forming another miter. Secure the mitered corner with a few small stitches, and continue sewing down the other side. Repeat on all corners.
Quilt Top Border with Mitered Corners
Supplies:
- Quilt top with squared edges
- Fabric for the border
- Fabric marking tool of your choice
- Quilting ruler
- Rotary cutter and/or fabric scissors
- Iron
- Sewing machine
- Matching thread
- Pins
Method summary:
This technique allows you to add a border around your quilt top with mitered corners. Unlike the previous techniques we covered, it will leave you with raw edges on the back of the fabric, so it’s suitable for quilt tops or other projects that will be lined.
Uses:
Adding a continuous border around square or rectangular pieces of fabric, like quilt tops or placemats.
Step-by-step instructions:
Step 1: Start by determining the length of your border pieces. You can use this equation to calculate how long you should cut each border piece: (the length of the side of the quilt) + 2*(the width of the border) + 4”. For this tutorial, I’m working with a 9” (23 cm) square, and I want my border to be 3” (7.5 cm) wide. So, the measurements of my border pieces are 3” (7.5 cm) by 19” (48 cm).
Step 2: Mark the centers of the sides of the quilt top, as well as the centers of the long edges of the border strips. You can use your fingers to lightly press a crease into the center of each side. Match the marks you made, and pin the border strips onto the quilt top.
Step 3: Using your quilting ruler, make a mark ¼” (6 mm) in from the corners of the quilt top. These points will mark where you will start and stop sewing.
Step 4: Sew the border to the quilt top using a ¼” (6 mm) seam allowance. Start on the first mark you made, ¼” (6 mm) in from the edge of the quilt top and finish at the second mark, ¼” (6 mm) before you reach the end of your quilt top. Backstitch at the beginning and the end.
Step 5: Repeat Step 2 on all sides where you want to add a border. When you’re sewing on a new border, lift the previous border up and keep it away from the new seam you’re sewing.
Step 6: Fold the quilt top in half diagonally, so that the raw edges of the two neighboring sides are on top of each other. Flip the seam allowances that are close to the corner up so that they are laying towards the quilt top rather than towards the border. Pin the borders and seam allowances into place to make sure everything stays flat and aligned.
Step 7: Using your quilting ruler, extend the 45-degree angle that is formed by your quilt top down towards the border strips. Another way to do this is to align the stitching line of one of the borders with the 45-degree line on your quilting ruler, and mark a line starting from where the line of stitching ends.
Step 8: Using a straight stitch, sew on the line you just marked, starting from the point that is closest to the quilt top. Start exactly at the point where the previous line of stitching ends to avoid any puckers or gaps forming at the corner. Backstitch at the beginning and the end to secure your stitches.
Step 9: Trim the excess fabric, leaving ¼” (6 mm) of fabric from the diagonal stitching line.
Step 10: Press the seam allowances of the diagonal seam open, and the seam allowances of the border pieces towards the border. Make sure there are no puckers and that everything is laying nice and flat as you give your piece a final press.
Tips:
If you want to add multiple layers of border around your quilt top, simply sew the different border strips together along their long edges first, and then follow the instructions above to sew the border around the quilt top. This way you’ll have perfectly aligned borders with minimal effort, and you can come up with some really fun and interesting designs using different colors, patterns, and widths of borders. This technique pairs well with striped fabric for the borders, which will give the illusion that the stripes are flowing in a continuous line around your quilt top.
Quick Q&A’s:
How much extra fabric do I need for mitered corners?
For methods 1 and 2, we’re only using the existing fabric, meaning you won’t need any extra fabric. You can simply divide your hem allowance in two, and mark your guidelines following this half measurement.
Methods 3 and 4 require you to add a separate binding piece, in the form of bias binding or binding strips. The length of the binding is equal to the circumference of your fabric, plus seam allowance to connect the two short edges of binding together.
For method 5, you can use this equation to calculate the length of the border pieces: (the length of the side of the quilt) + 2*(the width of the border) + 4”.
What to read next:
This article was written by Nisan Aktürk and edited by Sara Maker.
Nisan Aktürk (author)
Nisan started her sewing journey in December 2019 and already has a fully handmade wardrobe. She’s made 50+ trousers, 20+ buttoned shirts, and a wide array of coats, jackets, t-shirts, and jeans. She’s currently studying for her Sociology Master’s degree and is writing a thesis about sewing. So she spends a lot of her time either sewing or thinking/writing about sewing! Read more…