How to Make Half-Square Triangle Quilt Blocks from Two Fabric Squares

Posted by Christine Mann Apr 27, 2009

Supply List

• Quilting fabric
• Rotary cutter
• Cutting ruler
• Marking pen

Step by Step Instructions

See the photo labeled Step by Step Instructions below for a visual guide.

1. Cut two equal-size fabric squares, one light and one dark. The squares should be 1" larger than the finished size of the half-square triangle block.
2. Put the squares with right sides together.
3. Use a ruler to draw a diagonal line from corner to corner. (The Quick Quarter ruler from Quilter’s Rule or the Omnigrid Clear Marking Rulers can help make the marking go faster.)
4. Sew two seams 1/4" on either side of the diagonal center line.
5. Cut the blocks apart along the central line.
6. Square up the blocks and trim off the little tails from the corners.

You will end up with two identical half-square triangles.

Learn more ways to make half-square triangle quilt blocks.