Your quilt top is done and now it’s time to add a border.

One of the most popular is the mitered border, also called a Y-seam.

A mitered corner is one in which the corners meet in a 45-degree angle to form a 90-degree angle.

Mitered borders beautifully frame a quilt, and are good for directional fabric or when the quilt demands it, such as: Attic window and Eight-point star quilts, and Tumbling block designs.

The process of sewing these seams isn’t difficult at all.


Tip: Before adding a border, make certain each corner of the quilt top is absolutely square.

1. Start by measuring one side of your quilt top.

2. Next, measure the width of your border strip and double it.

3. Then add 4” to this measurement and cut the border strip to that length.

Example: If the side of your quilt is 40” and your border strips are 5 ½” wide, then 40 + 2(5 ½) + 4 becomes 40 + 11 + 4 = 55” length of strip to cut.


Tip: The key to success when sewing mitered corners is to stop sewing ¼” away from the edge of each seam and not sewing over or into any seam allowance.

1. Begin by folding your border strip in half crosswise and marking the center point with a pin.

2. With the wrong side up, place a dot with your fabric marker at each corner of the quilt, ¼” from top and ¼” from side.

3. Pin the side border to the quilt top, right sides together, matching the centers.

4. Working outward, pin the border strip to the side of the quilt. Excess border strip fabric (the tail) will extend beyond the corner edges.

5. Starting ¼” (dot) from the raw edge of the quilt top, sew the border strip to the quilt strip. Make sure you start and stop exactly at the marked pointes and never sew past your marked dots.

6. Press seam allowances toward the quilt.

7. Add the remaining borders in the same manner.


Tip: You’ll use the extra 4” tails to miter each corner.

1. Fold the quilt top in half diagonally, right sides together, to form a triangle so that the edge of the top border lines up with the edge of the side border and the resulting corner forms a 45-degree angle.

2. Line up the outside edges of the 2 border strips.

3. Place your ruler along the 45-degree angle created by the folded quilt top and draw a line with your fabric marker extending the angle onto the border.

4. Pin in place.

5. Beginning at the inside corner, sew the strips together, stitching exactly on the marked fabric line.

6. Trim the excess border (tails) to ¼” seam and press.

7. Repeat with the other three corners.

8. Press open.

BONUS: To see how to miter borders in action, Dena made a How to Sew Mitered Corners on a Quilt video for you.

Thanks Dena!