Ever since Kate Middleton first stepped out with Prince William, we've all been closely following her evolving fashion and trying to snap up her more affordable looks before they sell out. It's usually impossible! Then, at her wedding to her prince, her sister Pippa burst onto the scene in a dress that continues to be talked about. You know the one. There is now a continuing debate as to who is the best dressed. Maybe it shouldn't be a contest.

Each Middleton sister has her own style, which has only become more pronounced as their popularity has grown.

Here we're breaking down 10 of their key looks. Some formal, some more casual, all definitively British and definitely a style all their own. Kate prefers more classic looks with a modern twist, while Pippa is more adventurous with prints and since she's not a royal, we get to see her off-duty looks more often. The only question that remains is, are you a Kate or a Pippa, or a little bit of both?

20 Pippa: Honeymoon Bliss

When Pippa got married last year, photos from her wedding were printed in just about every paper, magazine and on every website imaginable. When your sister is the Duchess of Cambridge and you are a socialite with a killer figure, it is no wonder people want to track your every move. The paparazzi certainly didn't stop following her after her nuptials to James Matthews, in fact, the interest in her life has only grown since…

The newlyweds were snapped here arriving at Darwin International Airport in Australia in June of last year as they began their honeymoon.

She is positively beaming, no doubt still riding high on the fact that just had the wedding of the year. And we really can’t blame her after that fairytale wedding. It also helps that gets to fly on private jets around the world. Pippa is dressed casually in fitted jeans that show off her slim legs, but it’s really her ruffled top that landed this look on the list, as it brings a little bit of drama and a whole lot of fun to her ensemble. Her espadrilles are also perfect for the honeymoon that saw them jetting around to exotic locales. What a great life.

19 Kate: British Photoshoot

Wow. This seems like so long ago now. Kate was so fresh-faced and still Ms. Middleton at the time We have come so far from this photo. We should say Kate has come so far. Back then she was Kate Middleton. And today, well, you know. The transformation from commoner to Duchess of Cambridge has been amazing and looking back, you can see that even then she had a certain presence that would one day lead her to be royalty. This photo was taken in 2008 when she and Prince William were still calling each other “friends,” but most people and the press weren’t buying it and they were right not to. Just look at how things turned out!

Before she became a royal, it looks like Kate tried her hand at modeling.

This was taken at Blenheim Palace in England for the clothing company Really Wild. She does a feminine take on classic British styling here with her long tweed jacket and matching skirt, which is shorted to update the look and make it more modern. She looks radiant and clearly could have pursued that modeling thing if the whole marrying the future King of England thing didn’t work out.

18 Pippa: Wimbledon Chic

Pippa Middleton was spotted in this slinky dress while attending the Wimbledon tournament in London in the summer of 2017. Can you imagine what a cool life she leads? She gets to rub shoulders with British royalty and aristocracy on a regular basis, without any of the pressure to behave like a princess. It’s the best of both worlds! The dropped shoulder trend made the rounds from most designers last year and was scooped by every fashionista, Pippa being one of them.

But considering her impeccable style, she made sure not to succumb to a passing trend when she sported this look.

Always one to lead the trends instead of chasing them, Pippa’s mint green off the shoulder dress feels fresh and timeless and showcases her impeccably toned body without being too revealing. Paired with white sandals, this look epitomizes summer chic and is the kind of outfit that any girl would dream of having in her closet. At least I do…Everything about her look here has us dreaming of taking a trip to Wimbledon to get dressed up, watch a match and sip on some Pimm's. But this is all in a day’s work when you are name is Pippa Middleton.

17 Kate: These Boots Were Made For Walking

Uggs have really made a name for themselves since they first burst onto the scene in the early 2000s and it seemed like at one point in time that you couldn't walk more than a few feet without seeing a girl of a certain age wearing a pair. Don't get me wrong, I've owned several pairs and won't apologize for keeping my feet warm on those really cold days. But I don't think anyone is really arguing that they look particularly good. It's sort of understood that they're the ugly duckling of shoes or the necessary evil to keep your feet from getting frostbite in sub-zero temperatures.

Kate was no stranger to the trend of Uggs, which even made its way across the Atlantic at one time. And many wonder, including Who What Wear, whether Kate wearing them makes them 'royally approved.' Luckily, Kate's sense of fashion has come a long way since the days she used to wear Uggs. But even in this shot from her early days of fame, she still has her own sense of preppy/modern style. Here she's showing that she can be on trend without succumbing to the trend. She pairs her Uggs with skinny jeans and a polo-necked sweater than rather a Juicy Couture tracksuit because that would just be too much to handle.

16  Pippa: Undercover Duty

Pippa may have grown up outside the capital, but she’s been living in London for years and is now a bonafide city girl. She is often seen strolling around her posh neighborhood of Chelsea, beloved by royalty, socialites and bankers alike. But Pippa is the ultimate Chelsea girl at this point. Let’s be honest, even when she is just quickly running out to do some errands, she still looks better than most of us on a good day. It’s just one of the many perks of being naturally gorgeous and having a team of stylists and makeup artists at your beck and call.

While this is one of her most pared down looks to date, it isn’t really all that casual.

Despite the fact that she may be wearing scuffed white sneakers and a backpack, she still brings her fashion A-game by wearing a Red Valentino houndstooth coat with a cute peplum bottom ruffle. She was seen wearing this coat a lot, as reported in the Daily Mail. It immediately elevates her above commoner status, which she has certainly proved over the last few years she is not. The big dark shades and flipped hair give her that element of je ne sais quoi and once again we see why Pippa can make anything look good.

15 Kate: Headed To Work

Back in the day, before she was a full-time princess and lady of the people, Kate had a regular day job like most of us. But even then, it was clear that her days as a commoner were numbered. But flashback to 2007, when she was a buyer for the brand Jigsaw. Even then could barely go one day without being photographed by the press even when she was just Prince William's girlfriend. On this day, she was wearing a fun black and white dress from French Connection. She’s also upgraded from mainstream to high fashion since then. Another princess perk.

Back in the day, we could copy Kate's style without going bankrupt. These days it's usually a little harder to get the same look.

Fun fact, I remember my friend seeing her at a coffee shop once around this time and saying that even then you could tell by the way she carried herself that she would one day become Prince William's princess. Kate has always come across as poised regardless of what situation she was in or what question was asked, and that was before she was known the world over. She has always been elegant and polished.

14 Pippa: Long And Chic

This is just a stunning look from head to toe and Pippa pulls it off SO well. This is not her typical day to day type of look, but she totally makes it her own and we wish she would take more fashion risks like this. The dark navy paired with big flowers is a little mysterious, but totally enchanting and feminine.

According to the Telegraph, this pic was snapped at the restaurant Petersham Nurseries in Richmond, just outside London for a gala for the charity Too Many Women. On a side note, I’ve been to this restaurant a few times and the food is divine. But I’m pretty sure if when I ate there I saw Pippa at the next table, I would not have been able to eat my meal. I would have just been gawking! But I digress.

Pippa tends to wear her hair down and her casual up-do is such a refreshing change from her typical styles, not don’t we don’t envy her those glossy locks!

And doesn’t the look on her face just say it all? It’s like she’s thinking, “I know I’ve nailed my look tonight. Thank you.” When you hit a high note like this one, all that’s left to do is sit back and enjoy the night.

13 Kate: Pretty In Pink

When you are Kate Middleton, even before she was married to Prince William, she got to attend amazing events on a regular basis, like the Boodles Boxing Ball. I don’t exactly know what that is, but if it means wearing a gown like this one, sign me up. Back in 2008, Kate wore this bubblegum pink dress to attend the Ball and was photographed with a guy who was decidedly NOT her future husband, even though the two were dating at the time. Understandably, the photo was published in every corner of the globe including in the Daily Mail, who were already speculating on a royal engagement at the time.

It’s rare these days to see Kate dressed so va-va-voom, and looking back, this was probably one of the few times we saw her dressed this way. Once she and William became official and eventually started having kids, it’s understandable that her looks became more pared down. Interestingly, this ultra feminine and sexy dress is by Issa. That’s right, THE designer that created the dress she wore to announce her engagement to William. Even when she takes a more daring fashion turn, she has shown loyalty to a handful of particularly British designers for years now.

12 Pippa: Wimbledon Or The Italian Riviera?

Another year means another year to shine at Wimbledon. When you’re a Middleton, that means bringing your fashion A-game. This photo from last July was taken a few months after Pippa wed James Matthews. It looks like she was still in wedding mode, as her cream color dress hints at the one she wore on the big day. Although this short number is made for any kind of occasion, not just a walk down the aisle. This is a prime example of how effortless and chic Pippa makes her sense of style look. This dress could easily go from brunch in town to lunch on the Italian Riviera. It is no wonder that when she gets dressed and steps out heads turn.

The newlyweds attended Wimbledon last year and made sure to dress the part of one of the most fashionable couples of the year.

She was already sparking pregnancy rumors, according to Life and Style Magazine at the time. Although it wasn't until recently that it came out that she is indeed expecting a baby. Given all the press and attention she gets, it will only be a matter of time before people start making bets on the gender and name of their future child. And we’ll be waiting patiently to see how the little one adds to the family’s fashionable entourage.

11 Kate: The Royal Engagement

This day seems like only yesterday, doesn’t it? We could all feel it coming for awhile and the speculation mounted in the months ahead as to whether and when Prince William would pop the question to Kate. The announcement was made that Prince William was going to marry Ms. Middleton and the two released a series of photos to the world that highlighted the joyous occasion. All that was left to do at this point was sit back and wait for the wedding to happen.

This is arguably one of the most well-known dresses that Kate has ever worn and probably will ever wear. The Huffington Post reported that her dress sold out 'almost immediately' following the release of these photos.

You know the first one (her wedding dress!). It’s also the more attainable of the two, but you would have to find it first. Because the second photos were released from their engagement announcement, the dress flew out of stores, from online shops, you name it.

As a result of her single fashion choice, the British brand Issa was revitalized and put on the global map when Kate wore this dark blue knee-length dress. It was also the perfect complement to her sapphire and diamond engagement ring that once belonged to Princess Diana. It was a perfect way to honor such a legendary ring.

10 Pippa: Casual Ride Around Town

Last September, Pippa threw us a serious fashion curveball. Just when it seems like you might have figured out her style, she changes up the game. This time she decided to switch-up her usual look by seriously changing her hair. Having shorn off her usually longer locks, she debuted a long bob and a slightly lighter color. Was I the only one that was imagining what I would look like with this great haircut?!

She showed that she is a not opposed to taking fashion risks and chops off most of her hair!

And then she took a spin around London to show it off! It’s as if to say, “this is the new look, I dare you to say anything bad about it.” When really, there’s only good.

We might have said this before, but when Pippa goes 'casual' it's never really that casual. She is just able to give the appearance of nonchalance but the entire look is coordinated, even down to her lovely plum-colored leather bag that matches perfectly with her shirt. She may be wearing a checkered shirt and simple black skinny jeans, but it's all styled perfectly and she was ready for a day out on the town without any hassle.

9 Kate: Mother And Daughter Fashionistas

Sometimes toddlers don't want to walk. Sometimes adults don’t want to walk. It’s understandable. You get tired, you just want to take a break. But when you are a toddler who is a princess, you have to keep on going. Luckily, when you’re name is Princess Charlotte and your mom is Kate Middleton, she will sweetly pick you up and hold you in her arms when you need to stop going. The two are sweetly in sync as they wave to fans in the distance.

It’s amazing that with a toddler Kate is able to wear a cream-colored coat that has not one juice or snack stain on it.

Is Princess Charlotte a neat eater or is this one of those hidden perks of being royalty? You have people on standby who can come in with some stain remover the second you or anyone else spills on you. This is a classic look of Kate’s that we have come to know and love. She favors well structured and tailored coats, which she accentuates here with a diamond leaf brooch. It shows off her great waistline and she’s able to keep warm when she has to be outside.

8  Pippa: Church Service

Pippa knows that any occasion calls for a good dress, nice coat, fashionable hat, and heels. It’s this kind of look that has women the world over flocking to heritage British brands like Burberry to achieve or attempt to achieve this kind of classic British elegance. Pippa may be the more adventurous dresser of the Middleton sisters, but she definitely understands the need to sometimes play it a little more traditional. This is especially true when she’s walking alongside the Queen’s Lady in Waiting. Not the time to be bold.

On a typical Sunday headed to church last year, she stepped out in a military-inspired coat that had heads everywhere turning in her direction.

Even when Pippa decides to dress more traditional or conservative, she still adds her own personal touch. The hat is a feminine take on a masculine style, which makes the whole outfit a little bit more playful and offsets what could be a more serious look. Considering it was January and what looked like a cold, wet winter's day, we can only applaud Pippa for putting her legs on display in an above-the-knee dress and high heels. Oh, the things we will do for fashion.

7 Kate: Mommy Duty

How does she do it? Katherine never looks stressed. Not even in the face of a plane taking off behind her and her son being upset by the loud noise from the engine. She manages to pick little Prince George up for a cuddle to make him feel better, never losing the smile from her face and all while wearing stilettos. It’s adorable how their outfits coordinate and her navy blazer perfectly matches his shorts. It’s almost as if it was planned that way!

Most moms might be flustered in this situation, but not Kate. While many girls might dream of becoming princesses when they grow up, let’s be honest, would most of us really be cut out for the job? Probably not. There is a lot that goes into maintaining your poise no matter what the situation is or what jet might be taking off right behind you. Luckily, Kate is not most women, which is why she was able to become the Duchess of Cambridge and print her own brand of modern elegance to the role. She has excelled in this role from day one and her permanently camera-ready look is a perfect example of why she is perfect for Prince William.

6  Pippa: Psychedelic Print

Showing that she is not afraid to take the occasional fashion risk, Pippa did her best take on Swinging 60s London fashion by wearing this printed mini dress to attend Wimbledon two years ago. Wimbledon might be one of the most important tournaments of the year for professional tennis players, but socialites and fashionistas alike know it’s really about so much more. This is their time to shine sartorially-speaking. And when your name is Pippa Middleton, you are guaranteed to be photographed constantly, so the fashion stakes are high.

While she always puts her best foot forward, it was nice to see Pippa step outside her fashion comfort zone and wear something a bit more colorful and daring than her normal look.

This Tabitha Webb dress is a great example of how breaking from the norm can pay off big time in the fashion department. Hello! Magazine was one of many to give her 60s throwback dress two thumbs up. It’s also a great look that easily takes you from the sidelines of the courts at Wimbledon to cocktails later in the evening at a chic bar in Chelsea, where Pippa loves to hang out. Well done on another perfect look!

5 Kate: Lovely In Lavender

Shortly after their fabulous royal wedding, Kate and William stepped out together to attend the BAFTA awards in London and caused a big stir. At the time, there were rumors going around as reported by the Daily Mail, that she wouldn’t be allowed to attend the annual awards ceremony, for fear that she would outshine the A-list celebrities. But shouldn’t one of the big perks of being married to the future King of England be that you can go to any award show you want?! We all know how this ended.

Kate was not going to be intimidated out of having a fun night out with her husband, rubbing elbows with the stars. And good for her!

Showing she has serious brand loyalty and maybe also in honor of her wedding dress, she chose this breathtaking Lavender gown by Alexander McQueen to wear to the BAFTAs in 2011. Together, she and her new hubby (aka Prince William) showed exactly why they make such a good looking couple. He’s dashing in his tuxedo and she looks every bit the part of a princess in this flowing confection with a sparkly waistband. They really are a fairytale couple, aren’t they?

4 Pippa: A Day As A Trader

This outfit is such a breath of fresh air, and whenever I see celebs wearing jumpsuits like this, it makes me think it’s something I should attempt, but somehow it never comes out quite the same. I think it’s safe to say that I’m probably not the only one who has been in this situation. Maybe this is just another look we should leave to the celebs.

While Pippa tends to prefer wearing dresses and skinny jeans, we rarely see her in a riff on a business casual look like this tailored jumpsuit here.

So it was refreshing to see her take a break from her typical outfits of choice. This purplish-grey Reiss jumpsuit, paired with suede grey heels was the perfect outfit for the BGC Annual Global Charity Day in 2016 when Pippa spent the day on the trading floor making calls to raise money. She’s also shown time and again that she is a master of dressing for any occasion. The Telegraph even dubbed it a 'desk-to-dinner' look, and we couldn't agree more. When you’re surrounded by day traders, it’s time to go a little more serious and pull out an outfit that will have you be taken seriously AND still be incredibly fashionable. Doing work for a good cause has never looked this good.

3 Kate: Pregnant Glow

I can imagine that being a princess has many, MANY upsides. You get sent custom gowns by sought-after fashion designers and can attend any event you want. But it also means always being on duty. If you crave something like a French macaron, someone will probably get you one, straight from Paris. Or at least this is how I imagine I would wield my power as a royal.

While pregnant with her first child, Prince George, Kate was not let off from duties as a princess. She was snapped at a National Portrait Gallery event in 2013 wearing a beautiful sparkly blue cocktail dress by British designer Emilia Wickstead. And she looked absolutely radiant. In Style even said it was an ode to 50s glamour. Maybe part of this great look was the pregnancy glow everyone talks about.

On this occasion, she proved once again that she was born for this role. As always, she was poised, pretty and engaged regardless of the fact that she probably would have preferred to be at home, wearing sweats, and eating ice cream from the tub. Or maybe that’s just a stereotype of pregnant women. After all, Kate is the modern mom. She does it all and she makes it look easy and glamorous.

2 Pippa: The Big Day

Arguably any woman's most fashionable day is their wedding day. But it’s (hopefully) a look you only wear once. When you're Pippa Middleton and you know that billions of people are going to see pictures of your wedding gown, you have to make sure you look your absolute best. As reported in Glamour, she wore a custom dress by the famed British designer Giles Deacon, Pippa walked down the aisle in a one-of-a-kind cotton, silk confection that surely had her feeling like, well almost, a princess.

Everything else she wore was custom from her veil to the tiara and even her Manolo Blahnik heels with pearl accents. We're guessing those were real pearls...

There are always critics who like to draw comparisons between Kate and Pippa or accuse one of copying the other. But in this case, Pippa's really stood out from the one that her sister wore when she wed Prince William with all-over lace detailing. Despite typically taking more fashion risks, Pippa's dress was actually more demure than her sister’s, as she wore a high-neckline and only showed off her toned arms and a little bit of her back through a keyhole detail. When she walked down the aisle to marry James Matthews, she was definitely in a league all her own.

1 Kate: The Big Day

Was there ever a more famous wedding dress? Maybe Princess Diana's. But in recent memory, Kate's wedding dress that she wore to walk down the aisle at Westminster Abbey is likely to go down as the most famous wedding gown of all time. Still not convinced? Let's break this down, Kate's wedding dress has it's own Wikipedia page. Yes, the dress alone. She effectively changed the wedding dress game when she got married all those years ago back in 2011.

Her dress was designed by the British fashion designer Sarah Burton for Alexander McQueen and every detail about what she would wear to marry her prince was successfully kept under wraps until she was headed to the church on the big day. The News of the World reported that it was even kept a secret from the people who made the dress itself, as they were told it was being made for a TV show. Ah, the secrecy when you're about to marry royalty!

Aside from causing an inevitable buzz, Kate’s dress was perfection and she glowed while wearing it. The fit was immaculate and showcased her slim figure. Although officials would never confirm it, it was widely believed that the cost of the dress was around £250,000 or $340,000 U.S. You can always find a cheaper replica from some corner of the web if this is your style.

References: Daily Mail UK, Wikipedia, Life & Style, WhoWhatWear, Daily Mail UK, Telegraph, Daily Mail UK, Huffington Post, Hello! Magazine, Telegraph, In Style, Glamour, News Of The World

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