The Assembly Line Drop Waist Dress Sewing Pattern Review

As soon as I came across the Drop Waist Dress Sewing Pattern by The Assembly Line, I knew it was the ideal choice to recreate a dress I’d spotted in COS (pictured below). With its clean lines and minimalist silhouette, this style perfectly captures that effortlessly modern aesthetic.

This versatile sewing pattern offers three sleeveless variations: a top, a short dress, and a longer midi-length version. All three feature soft gathers at the front neckline and a delicate keyhole opening at the back, finished with a fine ribbon tie. For added functionality, the dress versions also include in-seam pockets, and the pattern even comes with a hack to add a dramatic ruffle hem for extra flair.

For my version, I chose to sew it in one of our beautiful Nani Iro organic cotton double gauze fabrics. I’d been waiting for the right project to use this design, and the Drop Waist Dress felt like the perfect match—its simple structure really lets the fabric shine.

I made a slight modification to the ruffle hack included in the pattern, opting for a deeper ruffle to better match the proportions of the COS dress I was inspired by. To do this, I traced the pattern pieces for the top version and added 9cm in length so that the gathered skirt would sit just on the hip.

The pattern gives you the choice of using pre-made bias binding, and I was initially tempted to use a plain black binding which would have contrasted beautifully with the fabric. But in the end, I decided to make my own bias binding from the same Nani Iro organic cotton double gauze. It was my first time making it, and I’m pleased with the result—though next time I think I’ll increase the pre-folded width by around 7mm for a slightly more generous finish.

As with every Assembly Line sewing pattern I’ve tried, the instructions were clear and easy to follow—even the optional ruffle hack was well explained. The Drop Waist Dress is rated suitable for advanced beginners, which I think is spot on. It came together smoothly and was a real pleasure to sew.

I’m really happy with how my Drop Waist Dress turned out—so much so that I’m already planning my next one. I think it would look fantastic in one of our Atelier Brunette cotton poplins, which would really enhance the volume and shape of the ruffle.

You can buy the Drop Waist Dress sewing pattern here, and explore our full collection of The Assembly Line patterns here.