How To Size and Sew An Adjustable Strap

Lisa Stewart adjustable strap tutorial

You want to modify a pattern and add an adjustable strap. You've never made one, but how hard can it be? Then doubt starts to creep in and questions arise. It's 12 am and you're itching to get this finished, but who can you ask and get a quick answer regarding:

  • How to attach it?
  • How long?
  • How wide?
  • What hardware?
  • How to do it?

Making a strap for a bag is pretty straight forward. For some of us, an adjustable strap has been known to cause headaches and temper tantrums - maybe even tears. (I'm convinced this is not only at my house).

Niki Tiefenthaler modified The Claire Shoulder Bag to have an adjustable strap

Last summer I joined the testing group for The Laila Weekender as the guinea pig for beginner bag makers. I was happily making good progress, and in that home stretch to being DONE - and then it was time to make the adjustable strap.

To be clear, sewing the strap is the same as any other strap. It's the hardware application that confounded me. I had to keep returning to the pattern pictures to make sure I was putting the hardware on correctly.

And one side of my strap looked better and I had deemed it the "top side" to show the most. As an afterthought, I'm sure marking that side as "good" would have been very helpful.

As I've told my children over many decades, let me save you some time and frustration by showing you how to avoid my mistakes. We're going to use the instructions from The Penelope Crossbody Bag with pictures and added tips. 


How To Attach It:

Not all designs easily have a place to add the connectors needed to add a strap. Generally, the strap connectors are added over the side seam for the best stability and how the bag hangs when being worn. This should be considered before constructing the bag so the necessary stabilizers can be added between the exterior and interior fabrics.

For a small lightweight pouch, like The Janie Pouch, this isn't quite as necessary because unless you plan to add some rocks, it probably won't be very heavy. 

Janie Pouch with tabs and rings for crossbody strap by Kristin Marshall Graves

No matter where you put the fabric strap connectors, you will need to be able to attach "D" rings or in the case of a pouch, some fabric loops.


How Long Should It Be?

The Penelope Crossbody Bag adjustable strap pieces are 60" long, which ends up finishing about 55" long. Depending on your fabric, this may need to be pieced, which we'll cover below.

I am 5' 2" tall, so I adjust a strap to about a 45" length, so there is 10+" for adjustment which looks attractive. I don't want the bulk of two straps over my shoulder. The 60" length should work well for most people, but for shorter, taller, personal preference, etc., you may need to adjust accordingly. For a small child, a shorter length is definitely suggested. And of course, an adjustable strap does not have to be used as a crossbody strap. 

Josette Skilling's Alyssa Hip Bag as a crossbody.

Drape a tape measure across your shoulder and mark where you'd like to carry your bag and then add how much you would like for adjustment. If you'll be carrying the bag over a variety of clothes thicknesses, keep that in mind so that you have enough to adjust. 


How Wide Should It Be:

Some things here that would determine this:

  • Size of the bag - generally, smaller bag, thinner strap
  • The hardware you plan to use 
  • Personal preference
  • How much fabric you have to make the strap

The fabric will be cut 4 times the finished width of the strap. For a 1" finished strap, cut the width at 4 inches, a 3/4" inch strap would be cut at 3". 


What Hardware is Required:

An adjustable strap requires:

  • one adjustable slider - the width of the finished strap
  • two d-rings for the strap connectors
  • two swivel clasps IF the strap is to be removeable slide adjuster hardawre

Slide Adjusters at

How to Make the Adjustable Strap:

First, is your fabric consideration. If you are using a cotton fabric, you will want to add interfacing to give the strap some body. 

Next, if your strap is cut in two pieces, like 30" each on The Penelope Crossbody, they will be attached as follows:

  1. Attach the strap pieces with a 45-degree seam, which will reduce bulk. Pin the two strap pieces perpendicular RST to each other. Mark diagonally, and then stitch.
  2. Trim the seam to 1/4". 
  3. Press the seam open. If using vinyl, cork, or leather top-stitch at 1/8” on either side of the seam, which holds the SA open and flattens the top.
After joining the two sections, make a strap as you would normally, it's just a much longer strap! Top-stitch the edges and get ready to add the hardware. The directions below are for adding a swivel clasp for a removable strap. If you do not want to remove your strap, attach your strap to the D-rings on your bag directly, rather than the swivel clasps.
Add the Slide Adjuster:

1. Slide one end of the strap through the slide adjuster and loop over the middle bar 1" - 2", depending on your desired finished. If you are just stitching the end and/or setting a small rivet, 1" or so is sufficient. If you are doing a larger strap or want to fold under the end for a clean finish, you will need to fold over more. This is where if you've determined one side of the strap is better, that it be on the outside loop. I recommend marking the other end on the "good side" with a small piece of tape. This photo is from a different bag with a side view of the slide adjuster. 

2. Take the other end of the strap and slide on a swivel clasp, then feed the same end through the slide adjuster.


3. Take the free end of the strap and slide through the other swivel clasp. Fold over 1" - 2”, referring to Step 1 above as to how much. Use the picture below to make sure you are folding correctly and that your "good side" of the strap is on the outside. 

And there you have it! All the information necessary for making the decision to add an adjustable strap and how to successfully make one. 



One last tip - no matter where the pattern designer has written the instructions for the strap, it is usually best to make it first while you're fresh and not in a hurry!

- - - - - - - - - - - -

How did my adjustable strap making end? I finished it, clipped it on the bag, and - surprise! - the underside of my strap looks great!

I am going to hang this tutorial above my sewing machine! (Feel free to print it out for your use, too!)

The Penelope Crossbody Bag is rated for a Confident Beginner. With two sizes, make one for the Little Miss in your life. More details on the product page.



Whether you are a beginner or an expert bag maker, we'd love to have you join our Facebook Pattern Group. Ask questions, give guidance and encouragement, share your makes, and join in the conversation.
Please feel free to comment, but be aware that Shopify doesn't offer a way for us to respond. If you have any questions email us at
We'd love to hear from you! 

Older Post Newer Post

  • Carolyn Newsome on

    I’m quite sure some of us have adjusted a bra strap at least once in our lives. That shoullder strap is just like that.
    Also, if you have are using leather and your machine refuses to accommodate it for the straps, cut 3" from each end and replace it with 3" of fabric the width of the cut strap with interfacing (SF101) on each end. After folding the long raw edges to the middle, fold the strap raw edges to the outside (The fabric makes a “W”.). Sew across the end with a .25" seam. Refold with the raw edges tucked inside; finish off any top stitching. Add slider/etc. and attach to the bag. You have a nicely finished end and a decorative area even when the straps fall down.

Leave a comment

Please note, comments must be approved before they are published