Forget the bikini, this summer is all about the swimming costume. Susannah Taylor puts one pieces to the test and marks them on style, cut and swimability

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Many of you will be relieved to hear that this summer is all about the one-piece swimming costume.  According to retail analytics firm Edited, swimsuits are selling out three times faster than they did last year, there are 20% more one-piece styles online, whilst the itsy bitsy bikini is down in sales. I'll be honest with you (and I don't mean to offend anyone) but for many years I have seen a ‘one-piece’ as ‘mumsy’ . As a 41 year old mother of two I have refused to wear one until now for fear of feeling old or that my bikini wearing days are over. I have an aversion of ruched middle sections, low cut legs, thick straps and tummy support systems and will wear a bikini I think until I'm 70. However this season the swimsuit has really grown on me -  having had a serious style makeover there are now hundreds of beautiful styles to choose from that are elegant, sophisticated and far from something my grandmother might wear.

But which ones can you actually swim in? There’s nothing worse than attempting front crawl (embarrassing enough) only to find everything has fallen out when you get to the other end or you are sporting a grand wedgie as you climb the steps out of the pool.

Out of the twenty or so that I tried, these are the best. Some might break the bank but I’ve also learnt that when it comes to swimming costumes, the price reflects the fabric and quality which can make a hugh difference to holding everything in and keeping it there. Unless you are 18 of course and then you can wear what the hell you like...

The Original Sexy Rashie by  Une Piece  £116

Best for UV protection, surfing and looking like you mean water business

Flatter ranking: 9/10

Style Stakes: 9/10

Performance Rating: 10/10

Created so you can surf, run around after your kids and swim hard without everything falling out, the sexy ‘Rashie’ as this style is known, is this summer’s ‘It’ swimsuit. I have one and I love it. I would alomost go as far as to say I feel slightly Bond-girl in it.  I have very pale skin and over the last few years really got into swimming (I had lessons, that’s another story but now I can actually do front crawl without dying), so it’s perfect for covering me up without me having to slather myself in sticky suncream.   I’m not the sort of person to get all ‘Baywatch’ on you, but if you are that way inclined you can lower the zip, however I love it because I feel fun and elegant at the same time. One word on the breast situation – I have to wear a bikini top under mine as there’s not enough support for my ‘girls’. If they could invent one with an inner support I would be most grateful.

The Absolue Swimmer by  Reard , £350

Best for looking like a Baywatch babe, holding in your middle and front crawl

Flatter ranking: 8/10

Style Stakes: 8/10

Performance Rating: 8/10

Louis Reard actually invented the bikini back in 1946, naming it after the Bikini atoll in the South Pacific. The brand has recently undergone a makeover and they have some really beautiful designs in amazingly supportive fabrics. The one I tried here is the Absolue Swimmer which has removable soft cups and an elasticated underbust band for holding everything up. Ruched ties on the hips means you can pull the swimsuit higher or lower on the legs depending on your preference and it's made out of a strong fabric that smoothes and flattens the tummy.  Perfect for both poolside posing and swimming lengths in, the only downside is the rather eye-watering price – it’s a lot of money to spend on something so small.

Loop Detail Print Swimsuit, £55  The White Company

Best for poolside elegance and a very flattering style

Flatter ranking: 10/10

Style Stakes: 9/10

Performance Rating: 7/10

The White company have always done really elegant, affordable looking swimsuits and this is no exception. It’s free from padded cups which I like because it has a more relaxed, natural style to it and the stitching under the bust holds everything in place no matter what size you are. The double strapped halterneck means everything is hoisted up nicely and when testing it in the pool, everything stayed firmly in place. Stylish, feminine and extremely comfortable this is a great affordable alternative to more expensive options.

The Nordic One-Piece,  Perfect Moment , £180

Best for badass watersports, training, bust support and elegant lines

Flatter ranking: 10/10

Style Stakes: 10/10

Performance Rating:10/10

One of the best swimming costumes I’ve tried. Perfect Moment started out life as a high performance but super stylish skiwear brand which has since expanded into swim and surfwear. Using bold, striking designs and durable hi-tech fabrics, every piece is designed to be highly functional and are guaranteed to turn heads on the beach. The Nordic One-Piece is my favourite swimsuit I think of everything I tried. I love the high neck and thin straps and what you can’t see from this picture is that it has a big cut-out hole at the back making it sexy too. With hidden bust support and the perfect cut on the hips (not too 80’s hi-cut, not too frumpy low), it ticks every box. If you want a swimsuit that lasts, and flatters this is worth every penny.

The Glo Swimsuit by  Sweaty Betty , £80

Best for swim training, bust support and

Flatter ranking: 7/10

Style Stakes:7/10

Performance Rating: 8/10

Sweaty Betty do a few racer back ‘serious swimmer’ one pieces, but I like this one because it looks elegant but does a functional job too. Simple navy blue with a jolt of neon orange on the halterneck, it’s a very flattering neckline and also includes inbuilt support for the breasts which are kept well in place come backstroke or butterfly which I can't do FYI). Whilst some swimsuits come up short in the body, this one comes up very long, so you might want to choose a size smaller than you think. Finally, one word of criticism – the ruching on the stomach isn’t for everyone, and I feel adds a dose of frump to a beautifully elegant swimsuit.

True North Marea One-Piece by  Finisterre , £80

Best for sporty surfer style and physical

Flatter ranking: 8/10

Style Stakes:8/10

Performance Rating: 9/10

Finisterre is a brand I have come across recently that’s born and based in Cornwall and has a huge committment to finding the most sustainable way of making their products. Creating everything from waterproofs to surfwear, most of their swimwear is made using Econyl which is, amazingly,  recycled yarn from sources including used fishing nets. The Marea swimming costume I tried is created also using responsibly sourced yarn and it is really very awesome indeed. With a racer back, it also has a big cut out at the back and a zip at the front that not only gives a cool surfer–chick vibe but ensures sure nothing jiggles or makes a break for freedom. Whether you swim lengths, surf the waves, paddle board, or just want to feel stylish but safe in a swimsuit then this is your new best friend.

Aqua/ Plum triangle one piece,  Heidi Klein , £150

Best for incredible streamlining, serious style and durability

Flatter ranking: 10/10

Style Stakes:10/10

Performance Rating: 10/10

This swimsuit would win the award for being the most stunning swimsuit I’ve ever tried. Made from tough, durable, double lined fabric (it’s reversible!), you can just feel the quality of it. It manages to smooth and streamline any lumps and bumps and the cross-over back means it won’t budge come backstroke or back flip. A truly beautiful style that I can’t fault. Worth every penny.