Strip Piecing Basics

Published: Jul 24, 2025 by Amy Smart · This post may contain affiliate links · 24 Comments

One of my favorite tips and tricks for faster and more efficient quilt making is using Strip Piecing. This process consists of sewing long strips of fabric together side by side and then rotary cutting across the strip set to create smaller units that are already pieced. Strip piecing is one of the best time-saving methods when it comes to quilting. I hope these tips will help you learn some simple basics to make piecing quilts with fabric strips most effective.

If you prefer learning through video, at the bottom of the post I have a YouTube video about strip-piecing techniques where I walk through and demonstrate many of the tips I describe in this post.

Best practices when sewing strips together

Strip-piecing is a great time saver when making quilts. But there are some important cutting and sewing tips that will make a big difference with the success and accuracy of your piecing.

Using a consistent ¼ inch seam allowance

This is an important one. Keeping your seam allowance accurate and consistent will make it so that sub-cut units are come out the right size - especially if you're mixing them with other sub-cut units. If you're sewing smaller strips together, you definitely want to make sure you're sewing with a scant ¼" seam allowance.

Since one of the pro's of strip-piecing is speed, it's also easy to start feeding strips through your machine and get careless about the consistency of the seam allowance. To help with this I recommend using a sewing machine foot with a guide edge - that way you can easily keep your fabric lined up against the guide. In the photo above I'm using the new Baby Lock snap on ¼" Quilting Foot with guide (part BLSO-QGF).

I also love using an adjustable seam guide that attaches to and extends out ahead of the foot itself. It's easier to keep an eye on how the fabric is feeding through the machine. (This attachable guide comes with the Baby Lock Accomplish straight stitch machine, but you can also buy separate attachable guides for your machine model. Check with your machine dealership.)

Another great seam guide option are these inexpensive magnetic seam guides that attach easily to the metal throat plate of a sewing machine and act as a physical barrier to help guide fabric and maintain consistent seam allowances. Again, super helpful for running long strips through your machine quickly.

Sewing methods for strip piecing to prevent shape distortion

Most strip piecing projects begin by sewing a set of strips together side by side. As you sew multiple strips together, they will begin to arc or "bow" slightly if you sew them all starting at the same end. This is because the sewing machine feed-dogs will pull the bottom piece of fabric differently than the top strip that glides with less resistance under the presser foot.

One way to minimize this "bowing" is to alternate directions the seams are sewn. For example, sew the first strip to the middle strip going one direction, then change and sew the third strip to the middle strip starting at the opposite end. If this is confusing or hard to visualize, check the video demonstration below.

After the strips are sewn together, press seams to one side. (I'm a side presser.)

Press seams from the top and use the point of the iron to make sure the fabrics are fully open and the seams are flat. I like to use a hot, dry iron so I don't distort the shape of my strips.

Accurate strip piecing using precut fabric strips

Quilt patterns using 2.5 inch precut strips are very popular. These strips are typically 2 ½" wide x Width of Fabric (40"-42") and are commonly called Rolie Polies or Jelly Rolls.

The one challenge they have is that not all precut strips are created equal and vary slightly from manufacturer to manufacturer. These precut strips typically have a 'pinked' edge to prevent fraying.

Tips for sewing with a Jelly Roll or Rolie Polie

Quick tip! Before you even unroll a Jelly Roll, run a lint roller over both flat sides. The pinking process does cause lint and using the lint roller before you even unbundle the precuts, will absorb the lint. Your clothes and your cutting mat will thank you!

Before you start sewing these precut 2.5 inch strips together, measure the width of one of the strips to find where the 2.5 inch edge officially lies.

Is it at the peak or the valley of the long edge of the strip? (You only need to measure one per roll as they'll all be the same. But if you open up a new roll, make sure to measure the width of one of those strips too as it may be different.)

Then you know where on the strip to line up your seam guide for a consistent seam allowance.

Tips for cutting your own straight strips

You also have the option of cutting your own strips to a variety of widths. Here are my tips for squaring up your fabric to accurately cut straight strips. In the process I will demonstrate a simple rail-fence 21" x 21" mini quilt project.

This quilt uses the very traditional Rail Fence block, a super-versatile quilt block that can be laid out in multiple ways to create many different designs. It's as traditional as they come, but depending on the fabric choices it can look very modern at the same time. And it's great practice if you're trying strip piecing for the first time.

Rail Fence strip-piecing shortcuts tutorial

Here are some important steps to take if you are cutting your own strips from yardage. The first important step when it comes to cutting straight strips is to square up the fabric edges. Skipping this step can result in a V-shaped strip instead of a straight one.

Don't just start rotary cutting strips off the yardage. Often the yardage can become distorted on the bolt, or perhaps the busy fabric-store-worker has just cut your yardage without time to see if the edge is straight or square. The first thing to do is to make sure the edge of your fabric is "square" - meaning there's a 90 degree angle from the selvage edge to the yardage edge.

Begin by matching up the selvage edges. You can see in the photo on the left that the edges are not matched up. After you match up the selvage edges you may need to re-press the center fold.

When your selvage edges are matched up, lay the newly-pressed center fold on the cutting mat with the fold closest to you and lined up along the bottom straight line marked on the cutting mat.

Put the edge you are going to trim on your right (if you are right handed… Opposite if you are left handed). Lay the long ruler over the fabric, again lining up a straight line on the ruler with the bottom fold. Using the rotary cutter, trim the un-even edge off the right side of your fabric, creating a straight edge at a 90 degree angle to the selvage edge. This is how you "square-up" your yardage.

Now you can cut straight strips from your yardage. Turn the fabric so the newly trimmed edge is now on your left side. (Right side if you are left-handed.) Again make sure the fold is lined up with the bottom straight line on the cutting mat. Lay the ruler over the fabric to measure the width of the strip you want and cut - this helps with accuracy. Measuring the strip's width with the ruler, rather than the mat, is the most accurate measurement.

For this little 21″ x 21″ Rail Fence mini-quilt cut three strips 1 ½″ wide x the width of the fabric from three different fabrics. Using the sewing techniques I mentioned above, sew three different identical sets with one blue, white, and yellow strip in the same order.

When strips are pieced and pressed, return to the cutting mat. Trim the selvage edges. Again, flip the newly squared edge to your left (or to the right if you're left handed) so you can use your ruler as your guide to get your new units cut accurately.

When you go to cut your units from the strip-set, place the ruler over the top of the strip-set and measure the desired width you want to cut. Lay a straight line on the ruler directly over one of the seams (see arrow in photo) to keep your strips square in the new unit. (Don't use the top or bottom edge of the strip-set as your guide as these edges will still bow slightly.)

Cut your units off the strip-set (in this case cut squares 3 ½″ wide). You will get 12 squares from each strip set, for a total of 36 squares measuring 3 ½″ x 3 ½″.

Important piecing tip: If your seam allowance is even just slightly wider than ¼", the height (measurement across your strip set) will be slightly smaller than 3 ½". If this happens cut the width of the unit to the same measurement as the height of the pieced-set.

This works when making any Rail Fence block or other one-block quilt, but will become more tricky if you are piecing together multiple different units (like in a nine-patch block - see below). So measure your seam allowance and keep it consistent!

As you cut units from the strip-pieced set, keep the straight line of the ruler lined-up on one of the seams. Because of the slight bowing of the strip-set, you will need to square-off the edge again after every few cuts. It's worth it to keep your units square!

After you've cut all of your units, lay them out six across by six down. By rotating the blocks, you can get a variety of designs.

This is the design I chose. Sew the squares into rows of six blocks each.

Press the seams toward the vertical blocks. This will help the seams to nest together when you sew the rows together.

For the borders, cut two 2″ x width of fabric strips from your yardage. Sub cut them into an 18 ½″ and a 21 ½″ strip from each strip. Sew the 18 ½″ strips to opposite sides of the pieced portion. Press seams to the borders. Add final 21 ½″ strips to the top and bottom of the quilt and press seams to borders.

Free quilt patterns using 2.5 inch strips

Here are a couple of modern and scrappy strip-piece quilt patterns using precut (or cut your own) 2.5" strips:

Rail Fence Tutorial Baby Quilt Tutorial

This free quilt tutorial will walk you through the process of making a strip-pieced Rail Fence baby quilt. (There is also a printable version with instructions for multiple sizes from Baby - King.)

You can find the quick Rail Fence strip pieced baby quilt tutorial here.

You can see more variations and options for strip-pieced Rail Fence-inspired designs on this Rail Fence Pinboard.

Using Strip Piecing for Nine-Patch Blocks

Strip-piecing can also be used to create smaller units that can then be sewn back together to create new blocks such as traditional 9-patch blocks.

Click here for instructions to make a 9-patch Irish Chain baby quilt.

Strip-piecing short cuts to make Irish Chain Baby Quilt

Another favorite strip-pieced block is in this easy, but eye-catching Pinwheel tutorial.

The options for using strip piecing are endless, but knowing these basic tips like keeping an accurate seam allowance, how to square-up your fabric before you cut strips, etc. will make a huge difference in the accuracy and efficiency of your piecing.

As I mentioned, in the video below I'll also walk you through all of the cutting, measuring, and strip piece sewing techniques demonstrated in this post. And if you're ready for some more advanced strip-piecing projects, check out the full Strip-piecing class on the Riley Blake YouTube Channel.