I'm a Swimming-Obsessed Shopping Editor—12 Functional Yet Fashionable Swimwear Pieces I Swear By for My Workouts

Tried and tested by the Marie Claire UK team.

model lying down wearing green swimming costume
(Image credit: The Vault)

If I could only do one type of workout for the rest of my life, it would undoubtedly be swimming. But despite it being one of my most frequent workouts, I have always had a severe lack of swimwear that I feel good in and can get me through 50 lengths without any mishaps, which is why tracking down functional yet stylish swimwear has become my mission.

Of course there are your basic athletic swimming costumes available, and while they're great if you're a dedicated swimmer that values performance above all else, those of us who prefer a more gentle swimming workout may want something that you feel good in too - particularly if you like to spend some time lounging pool-side before or after your lengths.

Similar to the best sports bras or best workout camis, I need investment swimwear that I know is in no danger of slipping out of place or falling down no matter what stroke I'm doing, that provides enough support around the chest, and I feel works for my shape and makes me feel good. When I feel good, I perform even better throughout my workouts and get myself into a better headspace.

As well as rounding up my own favourite pieces of swimwear, I've called on the expertise of Marie Claire UK's Senior Health Editor Ally Head, News Editor Jadie Troy-Pryde, and eCommerce Analyst Sophie Cookson, all of whom have put their respective swimwear through its paces during workouts and weekends away. These are the 12 pieces that we would recommend in a heartbeat, with your every need covered.

abercrombie bikini on a white sheet tested by marie claire

One of the swimsuits tested by team MC UK for this piece, from Abercrombie & Fitch

(Image credit: Future)

1. Best everyday swimming costume

vuori Encinitas One Piece

(Image credit: Vuori)

Vuori Encinitas One Piece

Reasons to buy

+
Very comfortable fabric
+
True to size
+
Minimalist but chic

Reasons to avoid

-
No adjustable straps

This is easily one of the most comfortable swimming costumes I have ever put on. I have tried lots of one pieces that are a nightmare to get into, whether that be due to the cut or the fabric, but this couldn't have been more different. It's buttery soft and went on with no effort at all, but still provided support around my chest and didn't move or slip even after swimming multiple lengths in the swimming pool. However, I will note that when I've worn it in wavy seas, it can move slightly. For that reason, I do recommend sizing down if you have a larger chest and want strong support. Although it's a more classic cut, the square neckline, low swooping back and higher leg cuts give it that little something extra that sets it apart from the overly-sporty options on the market. It's the ideal middle ground for swimmers who want to look and feel their best.

2. Best patterned swimming costume

sweaty betty riviera swimsuit

(Image credit: Sweaty Betty)

Sweaty Betty Riviera Swimsuit

Reasons to buy

+
True to size
+
Very supportive
+
Chic pattern

Reasons to avoid

-
Padding can bunch up - but can easily be removed

On the days when I want to do a longer or slightly harder swimming workout, this Sweaty Betty costume has been my go-to. I opted to take the removable cups out as they did bunch up and shift out of place when I pulled the costume on or off, but I still have plenty of support without them in. The higher cut neckline and adjustable straps mean that I can really tighten it up to ensure it stays on firmly, and it has a modest bikini line that is very comfortable. I love that the print makes this standard costume feel more special, and the subtle back cutout gives it that little something extra, too. With just the right amount of compression, it will suit both casual and serious swimmers. Plus, I've now had this for about a year and washed it countless times, and it still looks brand new. I would happily pay for this again and again.

3. Best planet-friendly bikini

Lamu Manda Bottom in Blue Polka

(Image credit: Lamu Swim)

Lamu Swim Manda Bottom in Blue Polka

Reasons to buy

+
Sustainable
+
Bust support
+
Fun print

Reasons to avoid

-
Cheeky cut may not be for everyone

"I wore this gorgeous two-piece to Brockwell Lido during the last heatwave and can confirm that it's one of my new favourites from independent brand Lamu Swim, which produces sustainable swimwear made from lower-impact fabrics and in bold, colourful designs. This polka dot number is super simple to throw on, double-lined, flattering, and functional. I did a few lengths to test staying power and was impressed - it didn't move at all. Buy for a cheeky-cut bikini bottom that's designed to make you feel your best for lazy, long beach days." - Ally Head, Senior Health Editor

4. Best strappy swimming costume

cdlp racer swimsuit

(Image credit: CDLP)

CDLP Women's Racer Swimsuit

Reasons to buy

+
Adjustable straps
+
Stylish silhouette
+
Versatile colour

Reasons to avoid

-
Fully open back

I really didn't expect this swimming costume to fit me right due to the thin straps and minimal back coverage, but I was so pleasantly surprised. It's a true elevated basic - it's understated but still special thanks to the criss-cross straps and exposed back. It's made from a soft Econyl® jersey that stretches nicely and provides a great level of support, which makes it a favourite of mine for holiday wear when I'll be doing a few lengths but not going too hard on my workout. The nature of the cut means it isn't the most suited to lengthy swimming pool sessions where you'll be doing multiple different strokes, but for a soft workout or if you're after a one-piece that isn't frumpy or too full coverage, it's ideal.

5. Best supportive bikini

abercrombie Curve Love Balconette Underwire Bikini Top

(Image credit: Abercrombie)

Abercrombie Curve Love Balconette Underwire Bikini Top

Reasons to buy

+
Extremely supportive
+
Adjustable straps
+
Sweet summer design

Reasons to avoid

-
Not as much coverage as a swimsuit

I rarely wear bikinis for my swimming workouts, but this may have swayed me. I was sceptical about following the size guide online, but it matched up perfectly to my bra size for a comfortable and supportive fit that genuinely feels like underwear. The high-cut bottoms also impressed me as they didn't move around or roll down, even when I bent over outside of the pool or twisted around. There was zero digging in, and the adjustable straps provided a customised fit. Plus, how gorgeous is this print?

6. Best triangle bikini

monday swim Palma Top - Honey Crinkle

(Image credit: Monday Swimwear)

Monday Swimwear Palma Top in Honey Crinkle

Reasons to buy

+
Superior quality
+
Washes well
+
Customisable fit

Reasons to avoid

-
Not much coverage

"I've been quite blown away by the quality of the Monday activewear, clothing and, most importantly for this article, swimwear. While their Palma design looks like your standard run-of-the-mill triangle bikini set, it's really superior quality, has excellent staying power and washes well, too. When testing, I really rated that the bikini top offered a fully customizable fit with adjustable sliding cups and adjustable halter, plus that the bottoms offered just the right amount of coverage. That said, if you prefer lots of coverage for your swimwear, this design might not be for you, but IMO it's the perfect beachside set for if you know your time will be divided between sunbathing, swimming and watersports." - Ally Head, Senior Health Editor

7. Best swimming costume for holidays

Cannes One Piece away that day

(Image credit: Away That Day)

Away That Day Cannes One Piece

Reasons to buy

+
Thick straps
+
Doesn't slip
+
Timeless design

Reasons to avoid

-
Expensive

"There are so many swimsuits out there that are reliable and functional for proper swimming, but it can be hard to find one that is aesthetically pleasing and flattering. The two-toned high-cut leg meant that I could do lengths in the pool without the bottoms riding up and me having to adjust it. Similarly, the wide length, adjustable straps meant that it didn't ride down while I was swimming, which can usually be really annoying. I love how timeless this piece looks, whilst also being environmentally friendly by using PYRATEX® Active 1 materials and also being comfortable to swim in for long periods of time." - Sophie Cookson, eCommerce Analyst

8. Best plain swimming costume

seafolly sea dive One Piece - Black

(Image credit: Seafolly)

Seafolly Sea Dive Scoop Neck Drawstring Side One Piece

Reasons to buy

+
Adjustable
+
Hidden support
+
Removable cups

Reasons to avoid

-
Thin straps

"I was dubious that I’d feel supported in this strappy swimsuit, but was pleasantly surprised by the strength in that cross-back drawstring (for reference, I’m a 34F and UK 14/16, and I tested a UK 16). It’s a great one piece for a leisurely swim - think gentle open water laps or holiday sea dips - and the material is both stretchy and sculpting. The ruching adds nice detail to the hips, and I also appreciated the ample bum coverage as I don’t love a thong cut." - Jadie Troy-Pryde, News Editor

9. Best stretchy bikini

bond-eye Gracie Balconette

(Image credit: Bond-Eye)

bond-eye Gracie Balconette

Reasons to buy

+
Stretchy fit
+
Doesn't dig in
+
Stays in place

Reasons to avoid

-
No adjustable back strap

"If you haven't heard of Australian swimwear brand bond-eye, let us put them on your radar. Designing crinkle swimwear in a range of shapes and sizes, I tested the Gracie Balconette and Scene briefs in red from their newly launched Bare Collection. I love that the range promises to redefine the line between swimwear, athleisure and ready-to-wear - who doesn't love wardrobe items that you can wear multiple ways, right? - plus, how gentle the seamless edges of the bikini were, excellent for sitting softly on, not digging into bare skin. The fabric is also next-level soft, offering unparalleled comfort that's also supportive and confidence-boosting, as you know the suit won't budge an inch." - Ally Head, Senior Health Editor

10. Best swimming costume for large busts

boux avenue Rivoli monochrome swimsuit

(Image credit: Boux Avenue)

Boux Avenue Rivoli Monochrome Swimsuit

Reasons to buy

+
Extremely supportive
+
Measured by bra size
+
Goes up to a G cup

Reasons to avoid

-
Very thick straps

Boux Avenue is one of the brands I recommend most when it comes to swimwear, as they go by bra sizes rather than the standard small, medium, and large. This is brilliant if you can never find swimwear to fit you, require extra support around the bust, or you want swimwear that looks and fits like underwear. I have this one piece in black, and it's easily one of the items I feel my best in. It fits my bust perfectly, offers a lot of support around my middle, and stays firmly in place no matter what. The vintage design is so chic, and it really does suit everyone. The thick straps mean it can be trusted to stay firmly on my shoulders at all times, and I love the colour accents that elevate the look even more.

11. Best tie-up bikini

away that day Palma Top - Red

(Image credit: Away That Day)

Away That Day Palma Top

Reasons to buy

+
Lasts very well
+
Supportive
+
Good colour range

Reasons to avoid

-
Slightly pricey

"This is my all-time favourite bikini - so much so, I've had mine for around three years now and have taken it on every holiday, beach trip or lido visit. Yep - it's fair to say it's had a fair bit of usage in the sea, swimming pools, saunas and more, and yet the quality is still as good as new, which IMO is seriously impressive. I love that the brand prioritises sustainable practices, but also that this Palma design in particular is super flattering and fashionable, not to mention genuinely stays in place and makes you feel supported during any activity. I've been swimming, snorkelling, and even kayaking in mine, and you almost forget you're wearing it, it's so seamlessly supportive." - Ally Head, Senior Health Editor

12. Best swimming shorts

Regatta Aceana Bikini Shorts

(Image credit: Regatta)

Regatta Aceana Bikini Shorts

Reasons to buy

+
Provides more coverage
+
Doesn't slip down
+
Very affordable

Reasons to avoid

-
Runs slightly small

I recently invested in a pair of these swimming shorts from Regatta, and they've been my most worn purchase of the summer. I was looking for bottoms that had more coverage than regular bikini briefs without being super long or baggy, and these do the job perfectly. The material is nice and thick with a good level of compression, and they don't slip down. I've worn them for all sorts of water activities, from wild swimming to even a water obstacle course, and they've held up fantastically. I went with my usual size, but as someone with a bigger bum and thighs, I could definitely have sized up for a slightly less cheeky fit at the back.

Amelia Yeomans
Junior Shopping Editor

Amelia is Junior Shopping Editor at Marie Claire UK. With a keen eye for lifestyle trends and a focus on quality over quantity, she is very clued up on the best products and brands on the market. She previously worked as a Senior Writer for woman&home, covering everything from product reviews and nail art trends to reporting on fashion weeks and the best-dressed celebrities at red carpet events.