As London Fashion Week returns, all eyes are on Paul Costelloe, now poised for a defining moment under the direction of William Costelloe, son of the brand’s late eponymous founder.
For more than 40 years, the British-Irish fashion house was synonymous with its visionary creator, and William’s new leadership signals a fresh chapter in its storied legacy.
Paul Costelloe pictured at his studio in London.
Paul Costelloe was famously the only designer to have shown at every London Fashion Week since its inception, with his show a beloved and consistent fixture as the event’s opener. In September 2025, he presented his final collection – an ode to the bold, colourful streets of 1960s Beverly Hills – fittingly titled Boulevard of Dreams.
At Boulevard of Dreams for SS26, Paul’s final show, the models were styled in Sixties-inspired silhouettes.
Renowned as a true couturier, Costelloe built his reputation on impeccable construction and luxurious fabrics, with a particular passion for Italian textiles. Trained at the Chambre Syndicale de la Haute Couture in Paris, he spent the 1960s working alongside Pierre Cardin and Emmanuel Ungaro, influences that left a lasting mark on his designs. While contemporaries such as Vivienne Westwood and Mary Quant captured London’s rebellious spirit, Costelloe remained devoted to classic couture silhouettes and timeless femininity.
His family announced his passing last November, stating they were “deeply saddened to announce the passing of Paul Costelloe following a short illness”. He died in London, surrounded by his wife and their seven children.
His son, William, now takes the helm as Creative Director, having collaborated closely with his father throughout his career. For the past seven years, he served as Design Director at Paul Costelloe, where he played a pivotal role in shaping the brand’s catwalk collections and guiding its expansive global portfolio.
Speaking exclusively to TheIndustry.fashion, William opens up about the deeply personal journey of stepping into this role following his father’s passing. “It’s incredibly personal. My father’s presence is felt in everything he built, and that brings both comfort and responsibility. For me, honouring his legacy isn’t about trying to replicate what he did, but about staying true to the values he believed in – craftsmanship, integrity and a deep respect for fabric and tailoring. From there, I allow myself the freedom to design instinctively and honestly, in a way that feels natural to me,” he explains.
William is recognised for his expertise in colour and material, a sensibility shaped through formal training in womenswear design and textiles at Istituto Marangoni in Milan. He also holds a Bachelor’s degree in Fine Art Painting from Camberwell College of Art and a Master’s degree from Chelsea College of Art in London, grounding his fashion approach in both artistic vision and technical skill.
“My artistic abilities are key to me. Much like my paintings, my design voice is rooted in structure and form, and in how a garment sits and moves on the body. That feels closely aligned with my father’s love of tailoring,” he says.
William makes his London Fashion Week debut later today with the autumn/winter 2026 show, scheduled for 12 pm at the Waldorf. While this marks his first outing at the helm, he brings with him the invaluable lessons learned from working alongside his father – principles that continue to guide his vision as he prepares to make his own mark on the LFW stage.
“My father had an incredibly strong vision, and that clarity is something I carry with me. Rather than changing things abruptly, I see this as an evolution,” he emphasises.
“I take forward his attention to detail, above all. He also believed deeply in commitment; in showing up season after season. That sense of dedication has really guided me as I’ve prepared for this show. I go with my gut instincts… they’re usually right!”
The collection is described by William as “a new beginning for the brand”, with new silhouettes that he has always been passionate about. “It reinforces what the brand has always stood for: strong tailoring, beautiful materials, and timeless design, while gently introducing a slightly more contemporary, sculptural edge.”
As for the inspiration, he adds: “Tailoring is my inspiration – I will be championing this moving forward. There is a sense of strength running through this collection. I hope the audience feels this moment of confidence and a celebration of the Paul Costelloe brand.”
In fact, these elements serve as a heartfelt tribute to his father’s influence. “The tailoring language, the discipline of the cuts, and the respect for heritage fabrics all speak to his influence. Knowing that these fabrics were selected by my father adds a quiet emotional layer to the collection,” William shares.
“The fabrics are also especially meaningful. Many were chosen by my father just before he passed, which gives them a very personal significance. There’s a focus on traditional British and Irish textiles. The colour pallet is confident and refined allowing texture and silhouette to take centre stage. There are big structured shoulders, sculpted silhouettes, precise constructions and cuts.”
While we eagerly await the collection’s debut, William confirms that the brand will continue to honour his father’s London Fashion Week legacy, maintaining the tradition of showing at LFW in the seasons ahead. “Fashion week has always been an important moment for the brand. It’s where ideas come together and where the brand speaks most clearly, so continuing that tradition feels very important to me,” he says.
On the wider brand ambitions, William shares his desire for the Paul Costelloe name to represent integrity, quality and relevance. “A brand that honours its heritage and confidence,” he notes.
Beyond the catwalk collections, his focus is on building on the brand’s established strengths. “Refining the product, ensuring consistency across the business, and nurturing the relationships that have supported the brand for so long. We’re beginning to look at new territories and product areas that feel like a natural extension of our strengths. Everything comes back to clarity, quality, and care,” William concludes.