Here are some of the stores I like for lingerie fabrics and trims. I live in the United States, so I mostly order from North America to avoid outrageous shipping costs. Below the list of stores in the United States, I will include a few stores that I have not personally ordered from, but I know they are reputable places for anyone who lives in other parts of the world.
United States
Sew Sassy has a wide variety of lingerie elastics, fabrics and trims. In my matte elastic video, I mention that matte elastic can be a bit difficult to find. The hot pink elastic I show in the video came from this vendor, and it is style E710.
Fabric Depot has many different fabrics, elastics and notions for sewing lingerie. They have basic fabrics (cotton/spandex jersey, lightweight powernet, lycras, etc) in many colors. They also have many different elastics, but only in basic black, white and nude. They do have fold over elastics in several widths, which come in a variety of colors. I have ordered several of their valu packs, both for fabrics and trims, and was very happy with the assortment I received. I have emailed them several times with questions, and their responses were very fast and detailed. Orders with Fabric Depot must be placed over the phone or by fax. You can order samples of just about everything.
Tailor Made Shoppe has beautiful bra kits, stretch laces, and all the elastics and findings for making bras. I have ordered a lingerie grab bag in the past, and was very pleased by the interesting range of fabrics I received. I really like the quality of the bra-making elastics, and the rings/sliders in multiple metal colors.
ArteCrafts also has beautiful laces and bra-making supplies.
fabric.com You can find just about any kind of fabric here, from quilting cottons to wool suiting. For sewing lingerie, I have ordered cotton/spandex jersey, rayon/spandex jersey, and scuba. I have seen power meshes and other fabrics suitable for lingerie, but haven't tried them out yet. The quality of fabrics can vary, so if you aren't sure then order a swatch.
Spandex World As the name implies, Spandex World sells fabrics with a high spandex content. I have ordered cotton/spandex jersey, nylon/spandex milliskin, and stretch mesh from them. I love the wide variety of colors they offer. The same fabric in each category can come in different weights, so be sure to check the listing if it is heavy, medium or lightweight.
Girl Charlee I love elegant floral prints, and Girl Charlee is one of the few places I have been able to find them. However, I have two notes of caution with this store. Firstly, I find some of their product names misleading. I was looking to buy printed cotton/spandex, and ordered some prints that appeared to be listed as cotton/spandex. When I received the fabrics, they definitely didn't feel as if they contained any cotton. If it had been one fabric, I would have just considered it my own mistake, but it was three fabrics. So take note that the listing might say "cotton jersey rayon spandex blend", but will probably be rayon/spandex. Not sure why they even list cotton in the name. I'm not an textiles expert, but in my eight years working in the fashion industry I got a pretty good feel for identifying fabric content by touch. The other note of caution is the fabric quality. Some of the prints I received were quite soft, and others as stiff as a board. They did soften up a bit with washing, but I think some people might be unhappy if they are looking for buttery soft fabrics. So why do I still order from them? I really love the style of florals they offer, and sometimes I just can't buy cotton/spandex prints for $15+/yard. I have never tried to contact customer service, but if you aren't sure of a fiber content I'm sure you could ask.
Lace Heaven has a wide variety of laces, elastics, ribbons, bows, buttons and more. These trims seem to be mill ends, so the colors can be a bit random. But I have ordered picot edge elastic, piping elastic, stretch laces and buttons and have loved them all.
Fabric Depot has many different fabrics, elastics and notions for sewing lingerie. They have basic fabrics (cotton/spandex jersey, lightweight powernet, lycras, etc) in many colors. They also have many different elastics, but only in basic black, white and nude. They do have fold over elastics in several widths, which come in a variety of colors. I have ordered several of their valu packs, both for fabrics and trims, and was very happy with the assortment I received. I have emailed them several times with questions, and their responses were very fast and detailed. Orders with Fabric Depot must be placed over the phone or by fax. You can order samples of just about everything.
Tailor Made Shoppe has beautiful bra kits, stretch laces, and all the elastics and findings for making bras. I have ordered a lingerie grab bag in the past, and was very pleased by the interesting range of fabrics I received. I really like the quality of the bra-making elastics, and the rings/sliders in multiple metal colors.
ArteCrafts also has beautiful laces and bra-making supplies.
fabric.com You can find just about any kind of fabric here, from quilting cottons to wool suiting. For sewing lingerie, I have ordered cotton/spandex jersey, rayon/spandex jersey, and scuba. I have seen power meshes and other fabrics suitable for lingerie, but haven't tried them out yet. The quality of fabrics can vary, so if you aren't sure then order a swatch.
Spandex World As the name implies, Spandex World sells fabrics with a high spandex content. I have ordered cotton/spandex jersey, nylon/spandex milliskin, and stretch mesh from them. I love the wide variety of colors they offer. The same fabric in each category can come in different weights, so be sure to check the listing if it is heavy, medium or lightweight.
Girl Charlee I love elegant floral prints, and Girl Charlee is one of the few places I have been able to find them. However, I have two notes of caution with this store. Firstly, I find some of their product names misleading. I was looking to buy printed cotton/spandex, and ordered some prints that appeared to be listed as cotton/spandex. When I received the fabrics, they definitely didn't feel as if they contained any cotton. If it had been one fabric, I would have just considered it my own mistake, but it was three fabrics. So take note that the listing might say "cotton jersey rayon spandex blend", but will probably be rayon/spandex. Not sure why they even list cotton in the name. I'm not an textiles expert, but in my eight years working in the fashion industry I got a pretty good feel for identifying fabric content by touch. The other note of caution is the fabric quality. Some of the prints I received were quite soft, and others as stiff as a board. They did soften up a bit with washing, but I think some people might be unhappy if they are looking for buttery soft fabrics. So why do I still order from them? I really love the style of florals they offer, and sometimes I just can't buy cotton/spandex prints for $15+/yard. I have never tried to contact customer service, but if you aren't sure of a fiber content I'm sure you could ask.
Lace Heaven has a wide variety of laces, elastics, ribbons, bows, buttons and more. These trims seem to be mill ends, so the colors can be a bit random. But I have ordered picot edge elastic, piping elastic, stretch laces and buttons and have loved them all.
Canada
Bra Maker's Supply If you want to start sewing your own bras, this is your one-stop-shop. Fabrics, high-quality elastics and trims, patterns, even the bra-maker's manual which is an excellent and extensive resource for bra-making. I really love that the colors are named by Pantone colors, so if you are ordering several types of trims you will know if they are going to match! I have ordered bra-making kits and underwires, and if I recall correctly, shipping to the US was not ridiculous. However, Sweet Cups Bra Supply is the US distributor if you want to avoid high shipping costs and live in the US.
Emerald Erin I love love love the Carmen underwires. They are the perfect shape for me! I made up a bra in one the wicking bra kits, and it is perfect in this Texas heat. If you make bras, there a wide variety of wires and has explanations on which wires suit different breast shapes.
Emerald Erin I love love love the Carmen underwires. They are the perfect shape for me! I made up a bra in one the wicking bra kits, and it is perfect in this Texas heat. If you make bras, there a wide variety of wires and has explanations on which wires suit different breast shapes.
United Kingdom
Sewing Chest I have not ordered from this website, but I know UK bra-makers who regularly order their materials from this shop.
Australia
Booby Traps I have not ordered from this store, but I have oogled many of their patterns. Very interesting styles of bras and other lingerie. Lots of fabrics, trims and kits to choose from.