Within days of Kate Middleton‘s engagement to Prince William, the phenomenon known as the ‘Kate effect’ emerged, highlighting her remarkable influence in driving sales and elevating brands.
Whether high street or high-end, jackets, dresses and earrings worn by Kate are almost always guaranteed to sell out – often within hours.
When the couple announced their engagement at St James’s Palace, interest in Kate’s outfit was immense.
Her royal blue Issa wrap dress not only disappeared from shelves but also led the company into administration as it struggled to meet demand.
Several brands, including Reiss, Beulah London and Faithfull the Brand, have experienced significant surges in popularity following her appearances.
Maternity label Seraphine, for instance, saw a 400 per cent increase in sales after Kate was spotted wearing one of its dresses.
Years later, the ‘Kate effect’ remains as strong as ever. Her support continues to have a profound impact on brands – big and small, luxury and affordable.
Despite Kensington Palace announcing it would no longer disclose details of Kate’s outfits, her latest Petar Petrov blazer still sold out.
Below, we explore some of the most striking examples of the ‘Kate effect’ in action.
Petar Petrov The Founder jacket
During her visit to the National Portrait Gallery this month, Kate sported the £1,163 Petar Petrov ‘The Founder’ jacket in a rich chocolate hue, layered over a turtleneck wool jumper and Max Mara pinstripe trousers.
Despite her efforts to shift attention away from her wardrobe, the blazer sold out within hours as fans rushed to recreate her effortlessly stylish look.
The blazer that Kate wore during a trip to the National Portrait Gallery this month sold out within hours, despite her wish to divert focus from her outfits
Issa wrap dress
After eight years of dating, William and Kate announced their engagement on November 16, 2010.
During their official photocall at St James’s Palace, Kate stunned in a royal blue Issa wrap dress, perfectly complementing her new sapphire engagement ring.
The £385 silk frock, inspired by designer Daniella Helayel’s couturier grandmother, sold out within 24 hours, marking the beginning of the ‘Kate effect.’
Unfortunately, the surge in demand led the brand into administration as it struggled to keep up with production.
Prince William and Kate Middleton announced their engagement on November 16, 2010, with the future princess wearing a £385 royal blue frock by Daniella Helayel
Needle & Thread Aurora dress
Kate dazzled in the Needle & Thread Aurora dress at the UK-Africa Investment Summit Reception at Buckingham Palace in January 2020.
The £435 embellished tulle gown sold out within a day and even amassed a waiting list of 700 eager buyers.
The Princess later rewore the dress in 2022 for her Together at Christmas carol service, further cementing its status as a wardrobe classic.
The princess wore the stunning Aurora dress by Needle & Thread to a reception at Buckingham Palace in January 2020
Ghost floral dress
In April 2020, Kate, William, and their children joined the Clap for Carers initiative, showing their support for NHS workers during the BBC’s Big Night In.
Standing outside Anmer Hall, Kate looked radiant in a £129 floral dress by Ghost.
The frock sold out in just 30 minutes, with the brand donating the proceeds to NHS Charities Together – yet another testament to the power of the ‘Kate effect.’
Kate wore a £129 floral dress by Ghost in 2020, which then sold out in 30 minutes, with the brand donating the proceeds to NHS Charities Together
Rixo Izzy shirt dress in zebra marble
Kate’s bubblegum pink Rixo dress, worn during her March 2022 tour of the Caribbean, caught the attention of royal watchers.
Unsurprisingly, the £245 ‘Izzy’ marble print frock sold out soon after her appearance, but was later re-stocked.
Kate wore a bubblegum pink Rixo dress during her March 2022 tour of the Caribbean
Rixo Izzy shirt dress in polka dot
For Prince George, Princess Charlotte and Prince Louis’ first day at Lambrook School in September 2022, Kate opted for the copper polka dot version of Rixo’s ‘Izzy’ dress.
This effortlessly chic autumnal piece, perfect for dressing up or down, flew off the shelves just as quickly as its predecessor.
When Kate donned the copper polka dot iteration of Rixo’s ‘Izzy’ dress in Sepember 2022, it quickly flew off the shelves
By Pariah Sabine hoop earrings
During her second public appearance of 2024, at the Wimbledon men’s singles final, Kate’s earrings caught the eye of keen observers.
The £400 ‘Sabine’ design from British brand By Pariah showcased an architectural twist on the classic hoop style, crafted from 14-carat gold vermeil and recycled sterling silver.
Naturally, Kate’s highly-anticipated appearance led to these earrings swiftly selling out and they were only available for pre-order.
During her second public appearance of 2024, at the Wimbledon men’s singles final, Kate’s earrings immediately caught the eye of keen observers
Reiss Shola dress
When Kate and William welcomed then-president Barack Obama and first lady Michelle Obama to Buckingham Palace in May 2011, she wore the Reiss ‘Shola’ dress.
The £175 bandage style sold out within hours, crashing the website as shoppers scrambled to get their hands on it.
In the US, the dress was purchased over the phone before stores even opened, prompting Reiss to issue a limited repeat order.
At the time, the brand’s founder, David Reiss, told MailOnline: ‘I could have issued a repeat order for that dress of 6,000, 7,000, but I wouldn’t dream of doing that. The Reiss woman does not want to be seen in the same dress as everyone else. I ordered only 600 more to be made.’
After Kate wore the Reiss ‘Shola’ dress, it was purchased over the phone before stores even opened, prompting Reiss to issue a limited repeat order
Zara off-the-shoulder dress
For a charity polo match in May 2018, Kate embraced summer chic in a £39.99 striped off-the-shoulder dress from Zara, paired with espadrilles.
As soon as pictures surfaced, fans rushed to buy the dress, causing it to sell out in every size.
In May 2018, Kate wore a £39.99 Zara dress to watch William take part in charity polo match in Beaufort
Seraphine Jolene dress
Kate’s first official portrait with William and baby George featured her in a fuchsia pink ‘Jolene’ maternity dress by Seraphine.
Priced at £49, the stylish and affordable dress sold out in just two hours.
The brand later reported a 400 per cent spike in sales following confirmation that Kate had worn several of its designs.
When Kate wore a fuchsia pink Seraphine ‘Jolene’ dress for her first official portrait with William and George, which sold out in two hours
LK Bennett Lasa dress
For the royal tour of Australia in April 2014, Kate selected the £245 LK Bennett ‘Lasa’ dress, featuring a painterly blue poppy print.
The elegant frock, with its flattering square neckline, sold out almost immediately and remained highly sought after when Kate rewore it in 2016.
For her royal tour of Australia in April 2014, Kate selected the LK Bennett ‘Lasa’ dress and complementary court shoes from the high street chain
Marchesa Notte tulle gown
Kate introduced New York-based brand Marchesa to royal fashion circles in April 2017, wearing a stunning £1,105 scarlet gown to the opening night royal gala performance of 42nd Street.
With its honeycomb pattern and balletic layers of tulle, the dress quickly sold out, prompting the brand to restock.
Kate introduced New York-based brand Marchesa in April 2017, opting for a stunning scarlet gown from the brand’s Notte line
Zara floral earrings
At the 2023 Bafta Awards, Kate gave her bespoke Alexander McQueen gown a modern twist with Cornelia James black velvet opera gloves.
However, it was her £17.99 cascading floral earrings from Zara that stole the show.
The high street accessory sold out instantly and was later listed on eBay for over £100.
Kate stunned at the 2023 Baftas, but it was her choice of jewellery that stole the show – a pair of rose gold cascading floral earrings from Zara, costing just £17.99
Accessorize Polly earrings
For a picnic at the 2019 Hampton Court Palace Garden Festival, Kate accessorised her Sandro dress with the £8 Accessorize ‘Polly’ petal earrings.
After making a second public appearance in them, the earrings quickly sold out.
In July 2019, Kate wore Accessorize’s budget-friendly ‘Polly’ petal earrings, featuring pink gem details resembling blooms
Topshop mini dress
On her 25th birthday, Kate was spotted wearing a monochrome mini dress from Topshop while leaving her Chelsea flat.
The £40 figure-hugging design, styled with opaque tights and knee-high suede boots, sold out within 24 hours.
The figure-hugging Topshop mini dress that Kate wore on her 25th birthday sold out on the company’s website within 24 hours
Temperley London Emblem dress
Kate debuted the Temperley London ‘Emblem’ dress at an Action on Addiction gala in October 2014 while pregnant with George.
The £595 black dress, with its intricate cut-out effect, sold out on the brand’s website in less than 24 hours.
Kate debuted the Temperley London ‘Emblem’ flared dress at the Action on Addiction gala in October 2014, when she was pregnant with George
Faithfull The Brand floral dress
During a visit to a children’s hospice in Norfolk in June 2020, Kate was the epitome of summer chic in a lilac floral dress by Faithfull The Brand.
The £180 ‘Marie-Louise’ frock sold out within hours, prompting the label to restock just five days later.
A £180 floral dress by Faithfull The Brand sold out hours after it was worn by Kate in June 2020, cementing her status as the world’s most influential royal style icon
Tory Burch Paulina dress
Kate wore a £450 Tory Burch open-knit dress to a playdate with Prince George during the royal tour of Australia and New Zealand in 2014.
The playful yet sophisticated ‘Paulina’ dress completely sold out after her appearance.
She later rewore it on World Mental Health Day in 2015.
Priced at £450, Tory Burch’s ‘Paulina’ dress incorporated a fit-and-flare silhouette and playful fringing. Naturally, it sold out completely after the royal appearance
LK Bennett Eugenia dress
During a visit to the Young Minds mental health helpline in August 2016, Kate opted for a striking £225 red LK Bennett dress.
Unsurprisingly, it sold out in record time.
When Kate chose a £225 LK Bennett dress for a visit to the Young Minds mental health helpline in August 2016, it sold out in record time
Reiss Larsson blazer
Kate embraced casual chic during a visit to RAF Brize Norton in Oxfordshire in September 2021, wearing the £285 ‘Larsson’ blazer by Reiss.
The beige double-breasted blazer sold out almost immediately but was restocked in time for Christmas.
Kate has since recycled the piece for engagements in 2022 and 2023.
Kate embraced casual chic when she visited RAF Brize Norton in Oxfordshire in September 2021, following a two-month summer hiatus