European royal households follow a protocol that shapes certain aspects of their lives, with one of the most notable being style. 

Royal wardrobes are defined by dress codes, restrictions, and even clever tricks that can be surprisingly striking. From sewing small weights into the hems of dresses so they do not lift in the wind, as etiquette expert Myka Meier once revealed, to keeping diamonds spotless by cleaning them with water and gin, a secret shared by Angela Kelly, the British designer and personal assistant to Queen Elizabeth II, in her book The Other Side of the Coin: The Queen, the Dresser and the Wardrobe.

Kate Middleton in a white blazer and sweater 
© Neil MockfordKate Middleton in a white blazer and sweater

“In the past, protocol dictated 90% of a royal wardrobe and had to be followed. Now it is the opposite,” stylist Noelia García Gallardo explains to ¡HOLA!, reflecting on how these rules have gradually become more relaxed thanks to figures like Princess Diana, one of the first to push against them, and the passage of time itself. “Today, they have a very defined style. They have built a brand around their image, one that feels much more approachable. They repeat shoes, jewelry, and clothing in formulas that work for them.”

That idea is perfectly illustrated in a very specific combination often worn by both Kate Middleton and Queen Letizia, using color to their advantage with a trick that is incredibly easy to replicate.

Kate Middleton, Princess of Wales visits the Family Action's Children's Trauma Therapy Service in Bradford, northern England on January 27, 2026.© CHRIS JACKSONKate Middleton, Princess of Wales visits the Family Action’s Children’s Trauma Therapy Service in Bradford, northern England on January 27, 2026.

Kate Middleton, Princess of Wales waves during a visit to Charing Cross Hospital in west London on January 8, 2026© ISABEL INFANTESKate Middleton, Princess of Wales waves during a visit to Charing Cross Hospital in west London on January 8, 2026

This approach is known as a chromatic column, a technique that elegantly solves any trouser outfit and comes in handy on those mornings when inspiration is lacking, especially when putting together a work look. It consists of choosing pieces in the same color family from the waist up, which for these royals usually means a blazer paired with a blouse, sweater, or T-shirt.

The Prince and Princess of Wales, known as the Duke and Duchess of Rothesay when in Scotland, before taking the ferry across the water to the Isle of Iona, on the last day of the royal visit to the Isle of Mull.© Aaron Chown – PA ImagesThe Prince and Princess of Wales, known as the Duke and Duchess of Rothesay when in Scotland, before taking the ferry across the water to the Isle of Iona, on the last day of the royal visit to the Isle of Mull.

The result divides the outfit into two blocks: the upper half in a single color, often echoed in the handbag and shoes, and the lower half, where there is more freedom to experiment with different types of pants and textures.

While the Princess of Wales tends to favor tailored suits, often in dark tones like black and brown with pleats and high waists, Queen Letizia leans slightly more experimental.

“Queen Letizia always aims to project an image of personality and strength, while also presenting herself as a contemporary and approachable queen,” fashion stylist Mónica Gallardo explains. “She likes to take risks with textures and modern cuts, while always maintaining an elegant and sophisticated coherence.”

Queen Letizia in Madrid wearing a black blazer and sweater paired with tweed pants© Carlos AlvarezQueen Letizia in Madrid wearing a black blazer and sweater paired with tweed pants

Queen Letizia and King Felipe VI at the Princess of Girona Foundation (2016)© Carlos AlvarezQueen Letizia and King Felipe VI at the Princess of Girona Foundation (2016)

We saw this in December during her appearance at the 16th NAOS Convention in Madrid, where she applied the chromatic column trick, choosing a black cashmere sweater from Falconeri paired with a blazer in the same shade. It was a simple choice that allowed her statement trousers to take center stage: a striking green tweed pair with distinctive metallic front buttons by Maje, which she had only worn once before, at Infanta Elena’s 60th birthday.

Queen Letizia at the National Sports Awards ceremony (2022)© Carlos AlvarezQueen Letizia at the National Sports Awards ceremony (2022)

The monarch has been relying on this practical color formula for over a decade. Back in 2016, she wore it during events for the Princess of Girona Awards, pairing a vintage burgundy velvet jacket by Felipe Varela, a piece she has owned since 2008, with a knit sweater and a bag in the same tone, and adding tailored gray pants.

Queen Letizia in Madrid (2024)© Carlos AlvarezQueen Letizia in Madrid (2024)

At times, the wife of King Felipe VI flips the formula, applying it to the lower half of her look by matching her trousers and shoes in the same color. This gives her the freedom to choose more distinctive blouses, sweaters, or jackets that add a special touch, without worrying too much about how to style them, because with this trick, there is little room for error.