Using Lingerie Sewing Patterns for Swimwear

Posted by Nicole Voegele

Hi. My name is Nicki and I can’t leave well enough alone! As soon as swim week was announced I was immediately thinking of all of the lingerie patterns I have purchased and sewn recently and how awesome those designs could be as swimwear. After trying to convince my trouble making self to use of one the many swimwear patterns I already own for over a week I gave in and ended up using not one, not two, but four lingerie sewing patterns to make my own swimwear mini capsule all out of Phee fabrics!

It was a whirlwind week of sewing but in the end I fell completely and totally in love with using lingerie patterns for swimwear and I am here to show you how you can do it too! The best part about using lingerie patterns to make swimwear? The patterns require minimum hacking but endless potential for unique and custom swimsuits!

Choosing a Pattern

First things first, we need a pattern to work from! When choosing a lingerie pattern to make into swimwear the main things you need to consider are fit (i.e. coverage) and support. I am a firm believer in people wearing whatever makes them happy but there are laws dictating how much of the body can be shown legally (bummer, right?!) so make sure you are choosing a pattern that won’t get you arrested (Unless that’s your goal. You do you boo.) and that you feel confident and comfortable in from the start, it will make all the difference in the end!

So what lingerie patterns lend themselves well to becoming swimsuits? In theory all of them but some will be easier than others to manipulate! Personally, I have had the best luck converting soft bra patterns, like the OhhLuLu Jasmine or the EvieLaLuve Willow bra, into swim tops and there are so many great free panty patterns available online that make great swim bottoms as well (Check out this post on for my five favorite free lingerie sewing patterns for some of them!). The use of underwires and channeling is an advanced lingerie technique so if this is your first experience sewing lingerie I would avoid those for now but just keep in mind that they are an option as you progress and underwire swimsuits are AHHHMAZING!

The second thing you are going to need to consider is support. Support can mean a lot of different things but for the purposes of keeping this easy let’s just focus on breast support for now. One of the biggest advantages of learning how to transform lingerie patterns into swimwear patterns is being able to use stronger elastics, underwires, and specific construction techniques to make the most supportive and flattering swimsuit possible for your unique body. If you fall on the smaller side of the breast spectrum this may not be as big of a concern for you but if you fall on the lager side look for patterns that have large under bust elastic, fuller breast coverage, and a wider back band to offer the most support. If tummy/bum support is more your game, look for one piece options, like the Jamie Bodysuit (pictured below) , or high waisted pantie options like Maxine from Evielaluve or the Ava Panties from OhhLuLu.

Adjusting the Pattern

No matter what pattern you choose, be ready to make a couple practice pieces (or more!) before cutting into your good swim fabric. Just like with any other kind of apparel sewing the right fit is key to a perfect product and not every lingerie pattern is going to fit every person right out of the package.

I would recommend making your first practice piece (or couple of pieces) for whatever pattern you choose out of the fabrics recommended by the pattern to get the general overall fit right and then make another practice piece, or two or three, out of swim fabrics before using your “good” fabrics. The stretch percentages between lingerie fabrics and swim fabrics can be very different, which could cause the swimsuit to fit differently than intended. There are some lingerie patterns I have had to muslin seven or eight times before getting the perfect fit so don’t get discouraged if it takes you a while, it is all a part of the learning process! Personally, I have found a consistent need for sizing up at least one size when switching from lingerie fabrics to swim fabrics when using lingerie patterns for swimwear. If you need help fitting bra or panty patterns the Bra Makers Forum group on Facebook can be a great place to ask questions.

Since many lingerie patterns are basically swimsuit shaped to begin with, you may not need to make any adjustments at all to make swimwear out of your chosen lingerie patterns beyond swapping out the types of elastic you use. If the pattern you choose calls for picot elastic, plush backed or regular, like most do I am going to very, very strongly encourage you to swap that elastic out for either fold over elastic (I like to buy in bulk from amazon) or swim specific elastic. Picot elastic just doesn’t hold up to salt or chlorine like these other types of elastic and nothing is worse than your beautiful swimsuit stretching out because you used the wrong elastic. Trust me.

If you are using swim specific elastic and can find it in the same width as the called for picot elastic you won’t have to make any changes at all to your pattern which is a total win and probably the easiest way to get started. If you can’t find the width of swim elastic that matches the width of the picot elastic, you will need to widen or narrow the pattern seam allowance to match the elastic you can find BEFORE you cut out your pattern pieces. Remember you will be folding the elastic in so you need to adjust twice to get the same end result. Example: If the pattern calls for ½ inch picot elastic and you can only find ⅜ inch swim elastic you will need to remove a total of ¼ inch of seam allowance from each edge where the picot elastic will be, ⅛ for the initial elastic attachment and ⅛ for when it is turned under and topstitched.

PS if you need help attaching swimwear elastic, check out this swim week SAL video!

If you don’t want to use swim elastic your next best bet is to use fold over elastic, or FOE. FOE is a great option for when you want a pop of color contrast, a sportier look to your suit, or are making something that will be fully reversible. Using this type of elastic almost always means altering seam allowance, however, which is off putting to some people but I promise it isn’t hard at all, again it is all about the math!

FOE doesn’t get turned in on itself like picot elastic does so if you can find FOE the same width as the called for picot all you have to do is take that same amount off your seam allowance. Example: if your pattern calls for ½ inch picot and you have ½ inch FOE elastic to use, then you need to remove ½ inch of each edge the FOE will be used on.

If you do not have FOE the same width as your pattern called for in picot you will need to remove the called for width plus or minus the difference in what you have versus what the pattern calls for. Example: The pattern calls for 1/2 inch picot elastic and you have ¼ inch FOE elastic, you will need to remove a total of ¾ inch seam allowance, ½ inch for the unturned area and ¼ inch for the difference in elastic widths.

Okay maybe it is a little complicated but that is what all those practice suits are for right?!

Beyond elastic, any other pattern adjustments you choose are totally up to you! You might consider adjusting the back closure of your suit top from a traditional hook and eye, which totally work and you do not have to remove if you don’t want, to a traditional swim style closure or adjusting to have no back closure at all. Or you may want to play with different strap options, crossovers, or widths to change the feel of your finished pieces in a big way or even mash different patterns to get a totally unique to you look. Both are super quick changes to any pattern but make sure you are practicing before you start cutting into those good fabrics!

So there you have it, the quick and easy breakdown of using lingerie patterns to make custom swimwear. If you have questions, I am always available to help but really there is no better way to learn than just to dive right in and get started! All of the patterns I mentioned above are tried and approved by yours truly so start with them if you are a bit nervous but have fun exploring this whole new world of sewing! Give it a try and I promise you be sewing your own swimsuits, and lingerie, in no time!

Want to see all seven of my Phee swimsuits from lingerie sewing patterns and how I made a completely reversible Made for Mermaids Mama Bridgette bikini top? Be sure to visit me at and let me know you came from Phee!

Sewing Swimwear for the Vertically Challenged

Posted by Mary Kaye Cole

Welcome again to Phee Fabrics Swim Week! I hope you are enjoying our blog posts here on the website and our posts in the Phee Fabrics and Phee Fabrics Sewalong FB Groups!I recently tested the Mairin Ladies Swimsuit by Sew A Little Seam. I used the Navy and White Matte Stripe Nylon Spandex and the Coral Nylon Spandex Tricot and came up with a very cute, somewhat nautical bikini with a ruffle neckline and bottoms that don’t accentuate my flat butt!

Easy Peasy! Right?





What in the world was a vertically challenged beginner swimwear sewing seamstress who loves ruffles but hates to sew them thinking when she signed up to test a bikini with a ruffle neckline? Apparently she was not thinking. But in the end it was a great learning process for which I am so grateful. Had it not been for the fact that I was testing, I might have gotten frustrated and walked away, giving up on fitting something that required altering multiple pieces. If I had given up and walked away, I wouldn’t be able to show you this photo of me walking away in my cute little somewhat nautical swimsuit! I crack myself up! Ignore me.

So this non-thinking, intermediate seamstress but beginner at swimwear sewing, pattern testing seamstress is going to share her bikini top fitting journey with you. Let’s start with all the things that make me vertically unique. I’m all of 5’ 2.5” on a tall day. I have a short shoulder to bust apex measurement, a high waist, a sway back and a short torso overall. We won’t talk about my horizontal challenges because that’s a whole different blog post!

Since this was my first time testing for Sew A Little Seam, I decided I should make the pattern exactly as drafted and written. Any time I test for a designer I’m not familiar with, I do this. Different designers use different blocks and that can definitely affect fit. Fit issues come up in testing…that’s part of why we test. But when I find myself having fit issues others aren’t having, that is when I start looking at my unique body and how the pattern fits in the areas affected.

When I made the pattern exactly as drafted, the first thing I noticed was that the binding for the ruffle neckline was way to long. So I shortened it. And I shortened it some more. Still I had this.

This was prior to adding the elastic to the neckline. The binding to elastic ratio was 1:1. To accommodate for my binding that was still too long, I shortened my elastic to slightly shorter than the binding. But that wasn’t enough. The straps felt loose and it pulled the armscye too high under my arm.

Isn’t that Raspberry Circular Knit gorgeous with that Black Circular Knit? Glad I have enough of the raspberry to make another like this! Off topic, I know. But Phee’s Raspberry Circular Knit is my favorite fabric EVAH!

Back to our saga…I talked with the designer about my concerns and she asked a few questions and came up with a solution that made me go “GAH!!!! Rookie mistake.” When determining what adjustments to make, I had completely neglected my vertical trunk measurement. My VT is 56 ⅝” but the pattern is written for a VT of 58 ½” – 60” depending on which of my horizontal measurements you are looking at. We decided I should take 1 ½” height out of the bikini top based on my VT measurement.

So that’s where I started. But when I folded my pattern piece to remove the height, I realized that wasn’t going to leave near enough room at the thinnest section of the back to accommodate the bra band elastic and a ⅜” seam allowance for the binding. So I used 1 ¼” instead. This is the area where I removed the height.

I thought all was good and I started construction. When I added the ½” elastic for the bra band, I realized once I folded this under I was going to be sewing my binding (and thus ruffle) on the bottom band of my bikini top. Not good. So I ripped out the ½” elastic (not the only ripping I did that day unfortunately) and used ¼” elastic instead. That turned out to be a good compromise. The thinnest portion of the back band is still thinner than the ruffle, but I think given the circumstances this was the best solution.

So I have my bottom band on and I get my bra cups sewn in. Time to baste on the neck binding and check that. With the neck binding basted in place, I realized I still needed to remove a small portion from the binding (and therefore elastic), but I kind of expected this considering (1) I have to make an adjustment in height from shoulder to bust apex in most patterns and (2) I had to remove a significant amount of length from the neck binding for my muslin.

Now for the easy part! I have all my adjustments made and all I need to do is sew on my elastic and ruffle/binding. Easy part my left foot! My sewing machine decided to show out! I adjusted tension, I rethreaded, I adjusted tension again, I even cleaned the bobbin area despite the fact that birdnesting is a sign of an issue with your top thread but I gave it a go, I rethreaded again and I adjusted tension again. This is the best she would give me.

That bitch!!! I finally gave up and said, “You win. I just cannot rip out any more bird nested triple stretch stitch today.” Luckily I have already finished the bottoms and actually didn’t have to make any vertical adjustments for the bottoms (or sew in any bird nested elastic stitching). I could have made a slight adjustment to the bottoms to accommodate my sway back and in the future I may. But I found that the cut of the crotch to provide enough coverage that I can adjust them slightly differently than I’m accustomed to when putting them on and they stay put without showing anything that ought not to be seen.

So anyway… I gave my sewing machine a stern look, tucked in all my loose threads, threw on my cute new somewhat nautical bikini with the bird nested top stitching and said “Hot Hubby let’s go take some pics!” And so we did!

Yay! You read the whole blog post! I appreciate that and hope you found my saga helpful. You deserve a one day sale on Black and white Stripes and yellow tricot.

Head on over to Phee Fabrics and buy your swim fabric, grab theMairin pattern at Sew a Little Seam and make those short girl adjustments!!! Or tall girl adjustments! Or whatever adjustments you need to make! Then post your beautiful suits in our Phee Fabrics FB Group! I bet they’d love to see them over in the Sew A Little Seam FB Group as well.

Happy Sewing!

Mary Kaye

Disclaimer: Some of the links in this blog are affiliate links. This means if you click this link and buy something I may receive a small portion of that sale.