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15 Fashion Rules You Should Know by the Time You’re 40

Updated: May 17, 2024

Fashion should be fun at every age—and with these tips, you’ll look better than ever.

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Coco Chanel was great at reminding us that age is just a number. “The age of a woman is not important: You can be wonderful in your 20s, amazing in your 40s, and stay fabulous for the rest of your life,” the iconic designer is quoted saying. Fashion can help us do that at any age, though the rules change slightly as we get older. That said, those rules aren’t about avoiding certain things when we’re no longer in our 20s or 30s. They’re about knowing how to maximize our look—something that’s also true when it comes to makeup.

With that in mind, we’ve assembled the 15 best fashion tips to help you play up your best assets during your fourth decade. From well-fitting undergarments to smart silhouettes, here is your cheat sheet for looking great at 40 and beyond. After you check out these suggestions, learn the style secrets of women who always look put together.

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Good fitting bra
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A well-fitting bra is essential

“I know it sounds simple, but you must invest in a high-quality bra that fits,” says Silvia Campello, co-CEO of Italian luxury lingerie brand Cosabella. “Your bra is the foundation of your wardrobe, and if it fits correctly, it will make you look and feel your best.” While bra shopping can be a jarring experience, understanding your body and how it changes over time can be a powerful exercise. “It can impact how we view ourselves,” she explains. That’s one of the reasons Campello thinks bra fittings are so important: They help women embrace every milestone their body reaches, as well as provide them with immediate feedback on what bra styles will accentuate their figure in the best way possible.

Most brands offer virtual bra fittings on their websites with easy-to-follow instructions. If you prefer to visit a store, undergarment experts will take your measurements and offer up the best styles to accentuate your assets. While you’re shopping, find a comfortable wireless bra to add to your undergarment arsenal. The cut of this Cosabella Triangle Bralette offers the right support without feeling bulky or restrictive. You can wear it under your favorite tops and the smooth mesh will go unnoticed.

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athleisure wear
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Only wear athleisure that hugs you in the right places

The temptation to live in our leggings and sweatshirts is very real, especially in coronavirus times. Just follow one golden rule to ensure that your choices make your body look its best at 40 and beyond. “You need workout pants that hug you in all the right places,” says Laura Berens, owner of Love + Fit. “High-waisted, non-slip workout pants help keep your leggings comfortably and securely above your hips with no sagging, slipping, or awkward shifting.” She also suggests good-quality materials that help smooth out and hold everything in.

Love + Fit’s Guardian Leggings offer a silicone “stay put” waistband grip that helps keep things in place. The compressive material is also strong and smooths out any imperfections.

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mature woman dressed sexy
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It’s still OK to be sexy

“We need to break the stereotypes that society attaches to women as they get older,” says Sapna Palep, co-CEO of luxury lingerie brand Journelle. “When you’re in your 40s, you have a better understanding of who you are than ever before, and you should express that boldly.” She would know a thing or two about that: Palep’s brand is made for women by women, and it’s been making wearers feel sexy for years.

Palep encourages women over 40 to embrace sexiness through one of the biggest trends this year: exposed lingerie. “Try wearing your lingerie as outerwear, layered with more tailored pieces to achieve the perfect balance,” she suggests. “In your 40s, give yourself permission to live by your own rules—it’s time to embrace and express what makes you you!” While you’re at it, stop believing these 40 things about yourself after 40.

How can you do this without making a fashion misstep? Don’t expose too much. For example, if you opt for a low-cut top and have a hint of lacy black bralette peeking out from underneath it, make sure your skirt is capped at a demure length. On the flip side, if you’re looking to rock a mini-skirt, go with a top that isn’t too revealing.

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woman looking for comfortable shoes
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Only wear comfortable shoes

Nothing can cramp your style more than ill-fitting shoes. Wearing shoes that fit properly will translate into a more confident walk, and confidence is truly your sexiest accessory. As we age, our threshold for foot pain changes. Remember rocking sky-high stilettos at 25? Now kitten heels might be more our vibe. In addition to paying attention to heel length, pay special attention to shoe width, since our feet tend to expand as we get older. But before you start tossing your narrow shoes, see if you can resize what you already own. Gadgets like a shoe stretcher will stretch a shoe’s length and width up to half a size. Comfortable shoes will do wonders for the way you are perceived when you sashay around a room. By the way, here’s what your favorite shoes say about your personality.

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stretchy fabrics
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Opt for stretchy fabrics that hug your curves

Gone are the days when women of a certain age had to hide their curves under tunics and oversized pieces. Hugging your curves with quality, stretchy, fabrics can help you achieve a more stylish and slimmer look. This combination also offers comfort, which should score high on your fashion list.

M.M.LaFleur’s Harlem skirt is made out of a luxurious knit that pulls on easily and conforms to your curves. It features a high waist with a band—two design perks that create a flat-tummy illusion and give the wearer an hourglass shape. “The bold, sparkly yarn and elegant side slits make it elevated enough for special occasions,” says Nyjerah Cunningham, brand stylist at M.M.LaFleur. “The fold-over waistband makes it comfortable enough for everyday wear. Comfort plus style equals everything!” Check out these other fashion secrets from personal stylists.

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shapewear
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Don’t assume shapewear is only for a big night out

Sure, we don shapewear under our fanciest dresses and cocktail attire, but who says we have to reserve them for special occasions? You can—and should—harness the magical smoothing and tightening powers of shapewear for everyday outings, too. Brands are coming up with novel solutions that are perfect for daily life. For example, if you avoid wearing white denim because it seems too unforgiving, slip on a pair of these capris from Spanx underneath them. Problem solved! Play around with a few shapewear styles for your various fashion issues, and while you’re at it, make sure you have the best shapewear for every type of dress.

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7 / 15
woman in cardigan
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Don’t be afraid of relaxed silhouettes

This rule isn’t about hiding under oversized clothing, which actually tends to highlight the things we are trying to minimize. This is about being comfortable and chic, says designer Amy Voloshin of Printfresh. But you should be strategic about your choices—and when to wear them. “I love a slightly oversized silhouette or cut when I’m at home,” Voloshin explains. “Some traditional loungewear can look disheveled or overly casual, so I prefer something that has a crisper look to it.” This is especially important if you’re having company over or you’re considering an outing in your comfiest clothes. A cozy, well-made cardigan, like this one from Nordstrom, can pull together and elevate your basic leggings-and-T-shirt combo.

As you get to a certain age, it’s also smart to consider what material your clothing is made out of. “Natural fibers help to keep your body temperature regulated, and wearing something cooling and lightweight can make hot flashes more bearable,” Voloshin adds.

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comfortable bra
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Don’t swap comfort for lift

As we get older, bra shopping can be a tricky negotiation. Sometimes it feels like a toss-up between comfort and lift—but it doesn’t have to. These days, bra designers better understand women’s bodies and have found novel ways to address those issues simultaneously. Thick and stretchy straps and customized back zones are just a few of the many attributes a well-designed bra can bring to the table. Spanx’s Bra-llelujah! line has loyal fans of all ages for a reason. Its bras, like this full-coverage option that has a front closure, accentuate your curves in the best ways possible and don’t look bulky under everyday wear. These are the 9 essential bras for everything in your wardrobe.

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adventurous swimwear
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Say yes to adventurous swimwear

It’s a common misconception that after a certain age, women have to hide behind cover-ups or wear a boring one-piece at the beach or pool. Not so! There are new rules for women 40-plus, and these include looking sexy in and out of the water. Look for styles that play with dimensions and have a peek-a-boo factor; cutouts can play with the eye and accentuate your best assets. Just make sure to apply (and reapply) sunscreen so that you don’t end up with some very strange tan lines. Stock up on the only sunscreen the FDA wants you to use.

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knee high boots
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Slim your legs with over-the-knee boots

Certain styles can seem like a faux pas waiting to happen and so unapproachable that even trying them on seems off-limits. But some bold styles can actually yield big surprises. Case in point: over-the-knee boots. This style actually directs attention below the knee and tricks the eye into slimming the whole leg. To achieve this look, opt for a boot that hits an inch or two above your upper knee area, and pair them with skinny jeans or sweater dresses. Pick a brand that has a stretchy and roomy top and you are on your way to the chicest cold-weather outfit imaginable.

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woman wearing belt at the waist
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Position a belt at your waist, not your hips

We’ve been conditioned to position belts at our hips because that is where traditional belt hooks are found. But this positioning creates an optical illusion that can widen us. Instead, slide your belt higher, at the waist, to create an hourglass shape that cinches your waist and accentuates your breasts and hips. How’s that for a double whammy? Wide belts are a particularly good idea since they will make the hourglass illusion even more pronounced.

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layered necklaces
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Layer accessories for a more youthful look

Certain looks are synonymous with youth, and that’s definitely true when it comes to playing with accessories. But our accessories game seems to get less and less adventurous the older we get. That’s a mistake! Tap into a layered style to achieve a youthful look. You don’t have to be an expert stylist to get this right—many brands offer pre-layered styles that are as easy to put on as one single necklace. This chunky, mixed-metal necklace from Nordstrom features multiple strands of different lengths, and it’s all held together by a single clasp. Pro tip: Make sure the necklace combination you choose lands right between the beginning of your breasts and your collarbone. This will draw eyes to your decolletage and help you flaunt a sexy style. Make your life easier by ensuring that your new necklace doesn’t get tangled when you’re not wearing it. Your jewelry box is one of the 30 things you can organize in under 30 minutes—and here’s how to do it.

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accessories
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Step away from that scarf

A lot of women bundle up in a scarf during warmer weather because they believe this accessory hides a perceived problem area: the neck. Don’t fall into this group—step away from that scarf! Adding on this unnecessary layer will actually create more bulk in the neck and chest area. Instead, pick a bold accessory above your neckline to draw attention to your face. Big drop earrings will do the trick, as will statement necklaces. Although necklaces sit in the neck area, they provide negative space around the collarbone, which can help slim and glamorize the whole area.

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sunglasses
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Never underestimate a good pair of shades

In addition to hiding sleepless nights and under-eye wrinkles, as well as protecting your eyes and the delicate skin around them from damage, sunglasses can jazz up an outfit like no other. You can also play with a frame’s shape to help accentuate your facial features. Cat-eye shapes slim your face, while larger frames can add volume to a gaunt jawline. Now that you’ve decided what shape you want to purchase, check out these stylish sunglasses with UV protection.

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two women wearing leggings
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Don’t swear off leggings

Although you’ve promised yourself countless times that you would cut back on the athleisure, now is not the time to swear off leggings. These stretchy pants got a bad rep as they migrated from a gym necessity to a closet staple. But when worn correctly, leggings can slim your legs. They are also incredibly versatile. Pair a shiny black pair with heels and a big sweater for a night out, or wear them with ballet flats and an Oxford shirt for a shopping trip. The “Perfect” Leggings from Nic + Zoe are, well, pretty darn perfect. Next, learn the simple fashion upgrades that will make you look expensive.

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