Queen Letizia, 45, looked smart in the white trousers which had been ironed with a sharp crease down the front.
A black and white checked elbow length top completed her outfit.
Mum-of-two Letizia topped off the look with a pair of white and navy stiletto court shoes from Magrit.
Keeping her accessories to a minimum, Letizia wore no bracelets, necklaces or rings – but did sport a pair of 18kt white gold and diamond earrings from Gold&Roses’ SKYLINE collection, worth €1,685 (£1,500).
Her hair was freshly blowdried, and she wore it in a side parting loosely over her shoulders.
She kept her makeup simple, opting for a brick red lipstick and bronzer.
Yesterday, the Queen joined her husband, King Felipe, to drop their daughters off for the first day of school.
Letizia looked fresh faced for the school run, and appeared to be wearing no makeup.
She wore a casual pair of white jeans and a linen jacket. Her hair was up in a low maintenance bun and she held her mobile in her hand.
Being seen in public wearing no makeup is unusual for the Spanish royal, who is mostly very well turned out with a full face of glamorous makeup.
Earlier this week was no exception, as the royal sizzled while attending a church service in a tight-fitted red midi dress.
The dress was burnt, dark red in colour, and clung to the 45-year-old’s enviable figure.
Coming to just below the knee, the stunning dress featured long sleeves and a high neck, suitable for the commemorative church service.
While it was plain in colour, the dress featured detailed panelling, and structured shoulders, including detailing down the arms and panels on the bust.
Letizia also takes style inspiration from other royals around the world. She wore a denim Carolina Herrera dress just days after Meghan Markle, the Duchess of Sussex, did in September.
The Duchess of Sussex paired the look with oversized sunglasses, a raffia straw clutch bag and cream heels.
The dress had a wide belt in the same denim as the main body of the garment, and a deep-v neckline.
Letizia’s version on the other hand had long sleeves, large cuffs and lapels, as well as pockets on the chest.
She also wore blue stilettos and carried a brown leather clutch bag.