There’s a reason why Catherine, Princess of Wales and Crown Princess Mary of Denmark draw so many comparisons. There’s their backgrounds, for one, both women who married into their respective royal families and quickly carved out reputations for their eloquence and dedication to social issues over the course of their career. But Kate and Mary’s approach to dress is another common denominator. Style aside, the royals share a wry understanding of the relationship between fashion, image and diplomacy. Their reputation as trendsetters emerges from this nexus, which they occupy effortlessly.

Perhaps it’s no wonder, then, that Kate and Mary often end up mirroring each other with their ensembles. Some instances will see them wear the exact same design on separate occasions; take for example the cap-sleeved, pastel Beulah midi dress, worn by the duchess at Wimbledon in 2020 and the princess in 2019. Other times, they’ll turn to different designers for a similar result: a pink power suit, a blue bodycon, or a belted polka-dot dress.

Here, as Queen Margrethe II of Denmark announces her abdication, paving the way for Mary to become the first ever Australian-born royal, Vogue looks back on 15 times the Duchess of Cambridge and Crown Princess Mary were royal style twins.

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Princess Kate (2020, 2023) and Crown Princess Mary (2019)

Beulah is the British label behind not one, but three of the dresses owned by the Duchess of Cambridge and Crown Princess Mary. This sweet, ’50s-inspired midi dress is a particularly notable example, worn by Kate to Wimbledon in 2020, and most recently in 2023, and Mary at a public engagement in 2019. The design, from the cap sleeves to the button-front bodice and set-in belt, is refined, but not overly polished—there’s a flirtiness in the flippy skirt and the sugary pastels. No wonder it’s a staple in both royal wardrobes.

Princess Kate (2023) and Crown Princess Mary (2022)

At the wedding banquet of Crown Prince Hussein and Princess Rajwa, Princess Kate wore a blush sequinned gown by Jenny Packham—the very same dress that Princess Mary had worn last year for her 50th birthday portraits. Kate owns the same silhouette in an emerald green as well, which she debuted on a royal tour of Pakistan in 2019, and then re-wore in 2021 at the Royal Variety Performance in Royal Albert Hall.

Princess Kate (2020) and Crown Princess Mary (2019)

This patterned blue Beulah dress with a contrast collar was worn by Kate a year after it was seen on Mary during her tour of Indonesia. Kate adopted a more formal approach, accessorising the dress with matching navy pumps and a sleek ponytail, while Mary paired it with flesh-toned flats and loose waves to suit her occasion. 

Princess Kate (2019) and Crown Princess Mary (2021)

The final matching look from the Beulah trio is this long-sleeved, olive green midi dress, worn first by Kate in 2019, and in 2021 by Mary in Denmark. Aside from the choice of belt—black crocodile for the duchess and narrow beige for the princess—and the line of custom buttons on Kate’s skirt, their ensembles are identical, though of course it is worn by each with their own distinctive personality.

Princess Kate (2018) and Crown Princess Mary (2015)

This lilac midi dress by Emilia Wickstead—aptly called ‘The Kate’—is a familiar one, and has been seen in different shades on the duchess since 2017, from navy to deep green. You might not be aware, however, of the fact that Mary wore the same design on a tour of Tokyo in 2015, styled with a half-updo in a baby blue hue. 

Princess Kate (2022) and Crown Princess Mary (2022)

The bishop sleeves, the crew neck, the sour tang of raspberry pink—it was impossible not to draw connections between the Duchess of Cambridge’s Stella McCartney number, worn on the balcony of Buckingham Palace for The Queen’s Platinum Jubilee celebrations, with a similar design sported by Mary at daughter Princess Isabella’s confirmation in May. 

Princess Kate (2019) and Crown Princess Mary (2018)

A coat dress may be one of the Duchess of Cambridge’s signature silhouettes, but she’s not the only royal who can pull it off. This navy style by Eponine bore a likeness to a knee-length coat dress in the same colour that Mary had worn a year earlier, in 2018. 

Princess Kate (2020) and Crown Princess Mary (2021)

The Duchess of Cambridge was spotted in this belted Emilia Wickstead shirt dress in July 2020, and last year, Crown Princess Mary wore a similar long-sleeved style in Milan—a piece she had previously worn, also belted, in 2019. Neither Kate or Mary shy away from patterns—classic black-and-white polka dots are a particular favourite, often seen on the royals at public engagements on a tea-length gown. 

Princess Kate (2012) and Crown Princess Mary (2012)

From the startling shade of cobalt to the presence of a silver circle pendant, there is little that separates these looks from Kate and Mary, worn in 2012, aside from the length of the sleeve.

Princess Kate (2022) and Crown Princess Mary (2018)

When Kate stepped onto the red carpet for the London premiere of Top Gun: Maverick in a black-and-white Roland Mouret Gown, we couldn’t help but recall an evening dress Mary had worn in Washington in 2018 that featured a similar, off-shoulder contrast neckline. One thing is for sure: when it comes to the art of glamour and formalwear, there is little the royals have not yet mastered.

Princess Kate (2022) and Crown Princess Mary (2022)

Both Kate and Mary are well-acquainted with the power of a pink suit. This year, the royals have each made appearances in the rosy shade, the Duchess of Cambridge choosing a slim-fitting jacket and trousers by Alexander McQueen while the Crown Princess of Denmark opted for a wider leg in a salmon hue. 

Princess Kate (2018) and Crown Princess Mary (2018)

It’s the distinctive, exaggerated sweetheart neckline of Kate and Mary’s ball gowns, worn by both royals in 2018, that catches the eye. The Duchess of Cambridge’s Alexander McQueen dress is long-sleeved and crafted from blue velvet, while Crown Princess Mary’s Søren Le Schmidt design is a shimmering red satin. Nevertheless, when styled with their tiaras, updos and royal accoutrements, the resemblance is striking. 

Princess Kate (2022) and Crown Princess Mary (2018)

Wondering what colour makes a great statement coat? Kate and Mary’s outerwear have you coveting teal. 

Princess Kate (2016) and Crown Princess Mary (2015)

A structured blazer and skinny trousers are a formula that both Kate and Mary rely on for their more casual workwear. Clearly, the royals were in the mood for monochrome in 2016 and 2015 respectively, even choosing to pair their looks with an updo for added polish.

Princess Kate (2016) and Crown Princess Mary (2019)

Perhaps Mary’s gown was more teal than the duchess’s true blue Roland Mouret design, but the parallels between these two dresses—from the body-conscious fit, to the cut-outs at the shoulders and the floor-sweeping hem—are too abundant to overlook. 

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