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Best Outfit Ideas For 21st Birthday

35 Flattering Pieces That Make Some Seriously Jaw-Dropping 21st Birthday Outfits

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Oh, the much-anticipated 21st birthday! For many, it's a rite of passage worth celebrating (you can finally order a drink at a bar!). While some people choose to throw a big birthday bash, others take it easy with a Zoom party or perhaps an elaborate dinner party. No matter what the plan is, one thing is clear: there needs to be a birthday look that rises to the moment.

Whether it's a formfitting midi dress with a side slit or a revealing cropped cardigan that'll pair well with sleek trousers, we found some undeniably chic pieces that dial up the sex appeal. Even if you're in a more conservative mood, there's a top, pair of pants, or dress in the selection for you. Scroll on to see.

Image Source: H&M

A Walk on the Wild Side: Zara Printed Short Dress

Go for a wild print that speaks to your playful side in this Zara Printed Short Dress ($40). The print alone has us sold, but the silhouette and fit are the cherry on top of the cake.

Image Source: zara.com
Zara Printed Short Dress
$40
from zara.com
Buy Now

A Classic Little Black Top: Sokie Collective One Shoulder Going Out Top

This slim-fitting Sokie Collective One Shoulder Going Out Top ($69, originally $98) will make a sleek impression at the next date night or friends' night out. The single-shoulder silhouette dials up the allure, while the overall design is versatile and easy to pair with laid-back denim jeans or polished skirts.

Image Source: shopbop.com
Sokie Collective One Shoulder Going Out Top
$69
from shopbop.com
Buy Now

A Compliment-Worthy Top: H&M Crop Cardigan

This H&M Crop Cardigan ($40) will turn heads wherever you go, because it's so distinctly chic and effortlessly elegant. The muted shade makes sure you can style it with everything, from tan tailored trousers to a structured midi skirt.

Image Source: www2.hm.com
H&M Crop Cardigan
$40
from www2.hm.com
Buy Now

For Day-to-Night Versatility: Zara Full Length Faux the '90s Leather Pants

These glossy Zara Full Length Faux the '90s Leather Pants ($50) will amp up any look, whether you pair them with an asymmetric top, a knit sweater, or a fitted blouse. They are professional enough for daytime work meetings or after-dark parties.

Image Source: zara.com
Zara Full Length Faux the '90s Leather Pants
$50
from zara.com
Buy Now

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Ruched Detailing: Nasty Gal Satin Cowl Mini Dress

The side strings of this Nasty Gal Ruched Satin Cowl Mini Dress ($24, originally $59) give it texture, while the satin fabric will likely feel soft to the touch. It will hug your curves nicely.

Image Source: nastygal.com
Nasty Gal Ruched Satin Cowl Mini Dress
$24
from nastygal.com
Buy Now

The Perfect Slip Dress: ASTR the Label Alva Body-Con Midi Dress

This ASTR the Label Alva Body-Con Midi Dress ($138) is a chic way to do lingerie-style dressing. It oozes femininity and confidence, and it's perfect for a night on the town.

Image Source: nordstrom.com
ASTR the Label Alva Body-Con Midi Dress
$138
from nordstrom.com
Buy Now

A Dress That's Made For You: Dress the Population Martine Stretch Crepe One-Shoulder Dress

This Dress the Population Martine Stretch Crepe One-Shoulder Dress ($148) makes a sleek, modern, and sexy statement in your closet. If it gets chilly, just wear it under a leather jacket or a trench coat, and you'll be good to go.

Image Source: nordstrom.com
Dress the Population Martine Stretch Crepe One-Shoulder Dress
$148
from nordstrom.com
Buy Now

A Corset-Style Top: Nasty Gal Recycled Rib Button Front Crop Top

This Nasty Gal Recycled Rib Button Front Crop Top ($9, originally $48) features a corset bodice and a plunging neckline for maximum allure. Whether you style yours with casual jeans or amp things up with sleek leather trousers, you will look effortlessly stylish.

Image Source: nastygal.com
Nasty Gal Recycled Rib Button Front Crop Top
$9
from nastygal.com
Buy Now

An Open-Back Statement: Nasty Gal Knitted Ribbed Midi Dress

Show off your back in an elegant way in this Nasty Gal Knitted Ribbed Midi Dress ($24, originally $59), which features a high neck, a relaxed silhouette, and long sleeves. Style it with strappy heels.

Image Source: nastygal.com
Nasty Gal Knitted Ribbed Midi Dress
$24
from nastygal.com
Buy Now

Guaranteed Crowd Pleaser: Nasty Gal Jersey Plunging Sweetheart Neckline Slit Front Midi Dress

The square neckline and relaxed silhouette of this Nasty Gal Jersey Plunging Sweetheart Neckline Slit Front Midi Dress ($24, originally $60) make it extremely wearable. Pair it with a dainty chain necklace or a chunky gold style, and finish with stiletto heels.

Image Source: nastygal.com
Nasty Gal Jersey Plunging Sweetheart Neckline Slit Front Midi Dress
$24
from nastygal.com
Buy Now

An Undeniably Chic Set: A.L.C. Eleanor Rib-Knit Cardigan

This A.L.C. Eleanor Rib-Knit Cardigan ($95, originally $395) is refined enough to wear on festive occasions yet still casually elegant for everyday moments. Pair it with the matching A.L.C. Logan Rib-Knit Flared Pants ($95, originally $395) for the ultimate chic set.

Image Source: saksfifthavenue.com
A.L.C. Eleanor Rib-Knit Cardigan
$95
from saksfifthavenue.com
Buy Now
A.L.C. Logan Rib-Knit Flared Pants
$95
from saksfifthavenue.com
Buy Now

A Slinky Silhouette: Lisa Says Gah Elenor Wild Hearts Long Sleeve Ruched Minidress

The psychedelic heart print of this Elenor Wild Hearts Long Sleeve Ruched Minidress ($138) makes it stand out, and we also appreciate that it's cut from a recycled mesh fabric. The silhouette is flattering, making the dress a perfect pick for a date night or friends' night out.

Image Source: nordstrom.com
Elenor Wild Hearts Long Sleeve Ruched Minidress
$138
from nordstrom.com
Buy Now

For a Special Occasion: OPT Gertie Dress

Reserve this OPT Gertie Dress ($82, originally $137) for dressy occasions like a hot date or office party. The asymmetrical cutout is unexpectedly playful, definitely dialing up the allure. Pair it with tall heeled boots or strappy heels.

Image Source: shopbop.com
OPT Gertie Dress
$82
from shopbop.com
Buy Now

Some Cutout-Shoulder Action: Enza Costa Silk Rib Angled Neck Midi Dress

This Enza Costa Silk Rib Angled Neck Midi Dress ($225) oozes sex appeal, confidence, and femininity. It's a great one to dress up or down, depending on the mood.

Image Source: amazon.com
Enza Costa Silk Rib Angled Neck Midi Dress
$225
from amazon.com
Buy Now

An Effortlessly Elegant Pick: H&M+ Lace-Trimmed Slip Dress

This H&M+ Lace-Trimmed Slip Dress ($35) oozes easy elegance, plus the fabric has a luxe appeal. Style it with a blazer for the office and on its own with mules for date night.

Image Source: www2.hm.com
H&M+ Lace-Trimmed Slip Dress
$35
from www2.hm.com
Buy Now

A Cool Print: AllSaints Melody Pembury Midi Slipdress

The print and silhouette of this AllSaints Melody Pembury Midi Slipdress ($155, originally $259) make it stylish and airy. Pair with sneakers for a laid-back look or low-heeled mules for a dressier appearance.

Image Source: nordstrom.com
AllSaints Melody Pembury Midi Slipdress
$155
from nordstrom.com
Buy Now

A Designer Piece: Christopher Esber Ruched Crop Shirt

Christopher Esber is one of the hottest designers of the moment, known for his feminine pieces that ooze easy elegance and sensuality. We're crushing on this Christopher Esber Ruched Crop Shirt ($336, originally $480), which we're planning to pair with high-waisted jeans for a semidressy look or leather pants for a more polished ensemble.

Image Source: shopbop.com
Christopher Esber Ruched Crop Shirt
$336
from shopbop.com
Buy Now

A Red-Hot Moment: Nasty Gal Wrap Front Satin Midi Shirt Dress

In a sea of wrap dresses, this Nasty Gal Wrap Front Satin Midi Shirt Dress ($40, originally $99) will definitely stand out. Cut in gleaming satin that will nicely hug your body without making you feel restrained, it will pair well with heels and a chunky gold necklace.

Image Source: nastygal.com
Nasty Gal Wrap Front Satin Midi Shirt Dress
$40
from nastygal.com
Buy Now

Not Your Average White Top: Zara Ruched Satin Effect Shirt

This Ruched Satin Effect Shirt ($50) is a fun twist on a typical white button-down, and it packs just as much day-to-night versatility. We like the ruched detail and easygoing fit.

Image Source: zara.com
Ruched Satin Effect Shirt
$50
from zara.com
Buy Now

A Classic Blazer: Zara Buttoned Textured Weave Blazer

This Buttoned Textured Weave Blazer ($119) will make you feel in charge, thanks to the structured silhouette and imposing presence. We love it paired with a matching skirt for a standout suit or with tailored trousers or jeans depending on the occasion.

Image Source: zara.com
Buttoned Textured Weave Blazer
$119
from zara.com
Buy Now

A Bold Look: Naked Wardrobe One-Shoulder Faux Leather Midi Dress

We can totally see Lori Harvey rocking this Naked Wardrobe One-Shoulder Faux Leather Midi Dress ($108), how about you? Channel your inner femme fatale in this fitted leather number that brings a shoulder-baring silhouette and sleek faux-leather finish.

Image Source: nordstrom.com
Naked Wardrobe One-Shoulder Faux Leather Midi Dress
$108
from nordstrom.com
Buy Now

A Printed Mini: Zara Printed Short Dress

We love a printed dress, so this Zara Printed Short Dress ($50) immediately caught our attention. It has a relaxed yet put-together air that makes it a winner in our books.

Image Source: zara.com
Zara Printed Short Dress
$50
from zara.com
Buy Now

An Outfit Repeater: Nasty Gal Recycled Ribbed Knitted Cut Out Midi Dress

This Nasty Gal Recycled Ribbed Knitted Cut Out Midi Dress ($15, originally $89) is cut in a soft fabric and features an unexpected bodice cutout that amps up the sex appeal. We guarantee you'll be repeating this outfit!

Image Source: nastygal.com
Nasty Gal Recycled Ribbed Knitted Cut Out Midi Dress
$15
from nastygal.com
Buy Now

A Seductive Style: Significant Other Monza Cutout Jersey Midi Dress

This sultry Significant Other Monza Cutout Jersey Midi Dress ($220) features front cutouts, signature drapery, and a slim fit, perfect for cocktails on a roof. It has an understated elegance that makes it ready for your next date or holiday night out.

Image Source: modaoperandi.com
Significant Other Monza Cutout Jersey Midi Dress
$220
from modaoperandi.com
Buy Now

For Maximum Allure: Minkpink Willow Ruched Jersey Dress

This Minkpink Willow Ruched Jersey Dress ($90, originally $129) will accentuate your figure, thanks to its lustrous knit and slinky silhouette. It will look great with mules or kitten heels.

Image Source: shopbop.com
Minkpink Willow Ruched Jersey Dress
$90
from shopbop.com
Buy Now

A Dreamy Statement: & Other Stories Off Shoulder Tulle Midi Dress

This & Other Stories Off Shoulder Tulle Midi Dress ($249) looks straight out of a fairy tale with its voluminous neckline and air of royal elegance. Save it for a fancy gala or a themed holiday party.

Image Source: stories.com
& Other Stories Off Shoulder Tulle Midi Dress
$249
from stories.com
Buy Now

A Taffeta Affair: Self Portrait Lace-Detailed Midi Dress

This lustrous Self Portrait Lace-Detailed Taffeta Midi Dress ($555) is cocktail ready. It features slightly dramatic puff sleeves, a pleated bodice, and ruched detailing for a flattering fit and polished look.

Image Source: modaoperandi.com
Self Portrait Lace-Detailed Taffeta Midi Dress
$555
from modaoperandi.com
Buy Now

A Green Statement: J.Crew Open-Back Silk Charmeuse Dress

The green jewel tone of this J.Crew Open-Back Silk Charmeuse Dress ($262, originally $328) gives it a luxe appearance, while the side slit amps up the sex appeal. It also features a head-turning open back, which makes it an all-around irresistible look.

Image Source: jcrew.com
J.Crew Open-Back Silk Charmeuse Dress
$262
from jcrew.com
Buy Now

An Elegant Top: H&M Rhinestone-Embellished Rib-Knit Top

This H&M Rhinestone-Embellished Rib-Knit Top ($35) is an easy way to look polished and put-together. Complete the look with leather pants or a slip skirt.

Image Source: www2.hm.com
H&M Rhinestone-Embellished Rib-Knit Top
$35
from www2.hm.com
Buy Now

Your New Favourite LBD: H&M+ Rib-Knit Dress

This H&M+ Rib-Knit Dress ($40) dials up the allure with the neckline, and we like the matching turtleneck piece if you opt for more coverage and warmth. The rib-knit fabric makes it look quite polished.

Image Source: www2.hm.com
H&M+ Rib-Knit Dress
$40
from www2.hm.com
Buy Now

For a Figure-Sculpting Number: Naked Wardrobe Hourglass Midi Dress

Flaunt what your mama gave ya in this flattering Naked Wardrobe Hourglass Midi Dress ($64). It will hug you in all the right places with its figure-sculpting silhouette, polished fabric, and charming hue.

Image Source: nordstrom.com
Naked Wardrobe Hourglass Midi Dress
$64
from nordstrom.com
Buy Now

A Standout Style: ASTR the Label Halter Neck Satin Maxi Dress

This ASTR the Label Halter Neck Satin Maxi Dress ($89) will move beautifully with every step thanks to its figure-sculpting silhouette. The ruched details, halter neck, and side slit all come together to create a sultry effect.

Image Source: nordstrom.com
ASTR the Label Halter Neck Satin Maxi Dress
$89
from nordstrom.com
Buy Now

For a Night Out: AFRM Adut Cutout Bodice Long Sleeve Mesh Midi Dress

You'll feel confident and sexy in this head-turning AFRM Adut Cutout Bodice Long Sleeve Mesh Midi Dress ($88). Complete the look with some thong sandals and a cute shoulder bag.

Image Source: nordstrom.com
AFRM Adut Cutout Bodice Long Sleeve Mesh Midi Dress
$88
from nordstrom.com
Buy Now

An Intricate Black Dress: Nasty Gal Satin Animal Jacquard Midi Dress

The subtle print of this Nasty Gal Satin Animal Jacquard Midi Dress ($24, originally $60) gives it visual interest, while the ruched bust and square neckline give it a feminine edge. Paired with your favourite pair of mules, it makes a decidedly polished, head-turning ensemble.

Image Source: nastygal.com
Nasty Gal Satin Animal Jacquard Midi Dress
$24
from nastygal.com
Buy Now

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