The New Year reception for the Diplomatic Corps accredited in Spain saw Letizia, 49, sport an emerald green satin skirt with a floral embroidered chiffon bodice.
Back then, Sofía styled it with a bow belt traditional jewellery and a small clutch bag.
Letizia, in what was probably a bid to modernise the look, paired the dress with a pair of earrings from Spanish jewellery brand Tous and used the belt without the bow.
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Spanish publication Vanitatis said of the royal’s fashion: “Letizia is committed to more affordable fashion than her counterparts, away from the big international firms.
“This formula has worked for her for years.
“In 2021, she has added an extra layer to it, introducing slow fashion into her wardrobe, which goes hand in hand with the small brands, mostly run by women, she frequently chooses to buy from.”
Taking advantage of her mother-in-law’s archive could be a key element in Letizia’s relatively low spending in fashion.
Recent data from UFO No More research showed Letizia was the royal who spent less on getting dressed for her duties last year.
Comparing her outfits with those of Queen Máxima of the Netherlands; Queen Mathilde of Belgium; Victoria, Crown Princess of Sweden; Mary, Crown Princess of Denmark; Mette-Marit, Crown Princess of Norway, and Kate, Duchess of Cambridge, it was found the Queen of Spain chose more affordable clothes for her official engagements than the rest.
While she was spotted with 111 new garments — the second-highest number among the eight women — on average, each of them cost less than the 119 pieces of Kate, who was the royal who spent most.
According to the figures provided by UFO No More, Letizia spent €301 (about £250) per purchase.