Creative director, Paul Costelloe
William Costelloe
William Costelloe is the son of Irish designer Paul Costelloe and was the house's design director for seven years. He was named creative director in January 2026, after his father died in November 2025. His first collection, for autumn/winter 2026 at London Fashion Week, focused on tailoring in Irish wools and tweeds and kept the house's emphasis on heritage fabrics.
Houses
Their runway, measured
44 looks in 1 showNext to every runway we track, William Costelloe's looks are less neutral, warmer, more colour-blocked and more matte.
Colours
- Chocolate brown · 3.9× the average23%
- Black18%
- Tan · 3.8× the average15%
- Beige / camel · 2.4× the average12%
- Ivory / cream · 2.0× the average11%
- Charcoal10%
- White2%
- Burgundy / oxblood2%
Share of garment area across their looks; × is against every runway.
Colour and surface
- Lightness40/100about average · all runways 39/100
- Colour saturation12.8about average · all runways 12.6
- Neutrals45%less neutral · all runways 60%
- Warm hues99%warmer · all runways 70%
- Tonal looks36%about average · all runways 33%
- Colour-blockingΔE 39more colour-blocked · all runways ΔE 35
- Surface texture5.35about average · all runways 5.06
- Sheen0.030more matte · all runways 0.065
What sets them apart
Shapes, fabrics and details they use far more often than other designers.
Silhouettes
- Inverted triangle / strong shoulder 77%4.2×
- Hourglass / cinched waist 52%5.2×
- Oversized 32%
- High-rise 23%
- Sculptural / architectural 20%2.0×
Materials
- Wool / tailoring cloth 68%2.2×
- Silk / satin 16%33% less
- Knit 14%30% less
- Jacquard / brocade 9%2.6×
- Mohair / fuzzy knit 9%3.6×
Details
- Padding / sculpted volume 73%5.2×
- Shoulder emphasis 73%3.9×
- Utility pockets 32%2.3×
- Gathering 30%2.0×
- Oversized collar 30%2.5×
Patterns
- Check / plaid 32%5.8×
- Abstract print 23%4.8×
- Colour-block 2%59% less
Mood
- Elegant 84%2.0×
- Powerful 80%5.3×
- Dramatic 45%3.4×
- Glamorous 32%3.0×
- Romantic 16%
Era references
- 1980s 57%10.0×
- 1960s 16%5.5×
- 1940s 16%12.4×
- 1970s 14%
- 1950s 9%3.7×
From the AI tags on 44 of their looks. A designer is credited with a house's shows while they lead it; ×: how much more often than across all 25,892 measured looks.
