Building Blocks: Learn to Make the Snowball Quilt Block


With their easy construction, simple piecing and minimal fabric requirements, snowball blocks are a solid choice for quilting newbs. They work well in a starring role, but also can do heavy lifting as filler blocks: definitely a quilt block you want in your arsenal. We'll show you how to make them, step by step.

How to calculate the size of a snowball block

First things first: what size block should you make? The snowball quilt block can be any size, really, but it's best when the finished size is divisible by three. So once you've decided on the finished size, do two quick calculations:

  • To calculate the size of the corner squares:  Divide the finished block by 3. Add ½". 
  • To calculate the size of the center square: Add ½".

To make it easier, here are calculations for the most common snowball block sizes:

  • 3" finished = 1½" corner squares + 3½" large square
  • 6" finished = 2½" corner squares + 6½" large square
  • 9" finished = 3½" corner squares + 9½" large square
  • 12" finished = 4½" corner squares + 12½" large square
  • 15" finished = 5½" corner squares + 15½" large square

For the step-by-step tutorial below, we're making a 6" finished snowball block.


  • Four 2½" corner squares
  • One 6½" square for the center
  • Rotary cutter
  • Cutting mat
  • Quilt ruler

Assembling the block

Step 1

Start by marking a diagonal line on each of the 2½" corner squares

Step 2

Arrange the corner squares to align with the corners of the center square, right sides together and with the diagonal lines you drew not pointing to the corner. Sew the corner to the larger square following the line you marked. Repeat for all four corners.

Step 3

Trim ¼" past the sewn line, cutting off the corners of the square. Discard trimmed pieces.

Step 4

Press all four corners open, pressing the seams toward the darker fabric.

That's it! You're done. A super-simple quilt block with endless design possibilities as well as size options.

This is a story of firsts: my first quilt, my first boyfriend and my first trip to the emergency room. (OK, technically my fourth trip, but who's counting?)
Suzy Williams
The world of quilting brings together a colorful patchwork of perspectives and people. And much like a top, no two are exactly alike. In our five-part series Patchwork Nation, we dive into the seams of that colorful community, connecting with five talented, artistic quilters — each with very different takes on quilting, creativity, and as it would turn out, life.
Create original one-block quilts with standout style. Discover the setting magic that lets you turn three versatile blocks into 30 dynamic quilt layouts.
Kate Colleran
Kate Colleran
Now Reading
Building Blocks: Learn to Make the Snowball Quilt Block