We all know the joy of finding the perfect t-shirt, something we feel comfortable wearing day in and day out. But just like most things, when it comes to your outfit… it's what's on the inside that counts. Your tee will look and feel best when the bra you're wearing under it is the best! That's why we pulled together our top 6 qualities to look for when shopping for your perfect t-shirt bra.

When it comes to your undergarments, the smoother the fabric, the smoother your t-shirt. Look for soft, silky fabrics such as nylon, polyester, and spandex. Bra technology has changed quite drastically over time, and newer fabrics such as spacer fabric (a three dimensional knit with an open weave) and memory foam (a foam which reacts to body heat, then molds to the body) are also a perfect underpinning to a sheer or thin t-shirt. Toronto stylist Talia Brown, whose clients range from Megan Markle to Sarah Lafferty, suggests going with a soft fabric and underwire to get that perfect shape, while staying comfortable all day long.

Left to right: GAP Low Cut T-shirt Bra, $42.95; La Vie En Rose Lightly Lined Sleekback Bra, $49.95; Addition Elle Flawless Tser Bra, $58

It's helpful to have a bra that can change its purpose as fast as you can change your top. Bras with j-hook convertible backs allow the wearer to cinch the straps to a racerback, for instance. Other bras, like Blush's Multi-way Longline Strapless, come with every function imaginable, including molded pads for full coverage, seven-way adjustable straps and a clean and sleek finish so you can wear it under even the most fitted garments.

Left to right: Blush Multi-way Longline Strapless, $38; Hanes Ultimate ComfortBlend t-shirt bra, $27.57; GAP Breathe T-shirt Bra, $42.95

When it comes to your everyday bra, you want something that will feel as comfortable in the morning as it will when you get home! Some things to remember: a wireless bra is ultimately more comfortable, and less seams mean a smoother looking shirt. If you have a larger bust, look for bras with wider straps for a more comfortable longer wear. Look for new technology, such as Wonderbra's Full Support Bra, which is designed to adapt to your temperature and activity to help keep you cool.

Left to right: New Balance for J.Crew sports bra, $60; Cosabella Never Say Never Comfie t-shirt bra, $70; WonderBra Full Support Bra, $19.99

Just because you need a bra with function, does not mean you have to sacrifice style. A lace detail or print peeking through a keyhole back or cropped tee adds a touch of personality and style to your average t-shirt look. Christina Remenyi, Owner and Designer of Fortnight Lingerie certainly encourages a more light-hearted approach to layering innerwear and outerwear. "[We] feel that any bra can be a t-shirt bra, even if it does show through. There's something so beautiful and confident about a black bra under a white t-shirt," Remenyi said.

Left to right: Fortnight Ivy Longline bra, $120; Marshalls Lace Bra, $16.99; La Perla Souple Push-up Bra, $244.33

The most crucial tip to finding the perfect bra is finding the right fit. "An overwhelming amount of North Americans are actually in the wrong size bra," says Rachel Avery, founder of Kallone Intimi. "The band should be tight enough on the loosest hook to only fit 2 fingers between the clasp and your back." Avery also suggests paying attention to your cup size. "Ideally the cup should sit flat, and there should be little to no visibility on where the cup ends and the remainder of your breast [begins]." Her top pick is the Implicite Neon Spacer Plunge Bra, which is perfect for t-shirts and "so light you forget you are wearing it."

Ask any expert, finding a bra that matches your skin tone will make it disappear even under the thinnest white tee. Jennifer Klein from Toronto lingerie boutique Secrets From Your Sister agrees: "Find a bra that matches or is a shade darker than your skin tone," she suggests. "This will allow you to wear the bra under light colours without seeing it at all. When a woman wears white it 'glows' under the light colours. This is a lingerie faux-pas for t-shirt bras!"

Left to right: Victoria's Secret Perfect Shape Bra, $54.70; Calvin Klein Icon Modern t-shirt bra, $56.36; WonderBra Wire Free Seamless Bra, on sale for $29.25

Nadia Pizzimenti is a Toronto based Fashion Stylist with Judy Inc.