[1] In 1918, the Lews Estate, including the castle, was bought by industrialist Lord Leverhulme from the Matheson family.

During the Second World War the Castle was taken over as accommodation for air and ground crew of 700 Naval Air Squadron, which operated a detachment of six Supermarine Walrus aircraft from a slipway at Cuddy Point in the Grounds.

On 22 November 2011 Lews Castle was awarded £4.6 million by the Heritage Lottery Fund to enable it to be converted into a bilingual museum and cultural centre.

In 2016, the ground floor of the castle, including a restored ballroom and a cafe, reopened to the public.

In 2017, Natural Retreats, a luxury holiday property company, opened apartments in the castle.