The 15-year-old passed the entry tests and will study the International Baccalaureate program for two years at the UWC Atlantic College in the Vale of Glamorgan, Wales.
It comes after fellow heir to the throne Princess Elisabeth of Belgium graduated from the college in May 2020.
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In a statement released from the Spanish court, it was confirmed that Princess Leonor will reside at one of the eight boarding houses on the campus.
The cost of the £67,000 course will be paid for in its entirety by King Felipe and Queen Letizia.
UWC is set in the 12th century St Donat's Castle on the southern Welsh coast and campus facilities include a library, woodland, an indoor and outdoor swimming pool, and classrooms within historic buildings.
It was founded in 1962 by German educationalist Kurt Hahn, who also set up Gordonstoun boarding school in Scotland, famously attended by Prince Charles.
Its website states that the college "provides a platform for young individuals to learn through shared experience and be empowered to make a positive difference".
The Spanish royal family
Princess Leonor was born on 31 October 2005 in Madrid. When she ascends the throne, she will be Spain's first queen regnant since Isabella II, who reigned from 1833 to 1868.
She also has a younger sister, Infanta Sofia, born in April 2007.
Felipe, who married TV news journalist Letizia in 2004, became king of Spain in 2014 following his father Juan Carlos I's abdication.
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