Old Swinford Hospital school (OSH), one of only two state boarding schools in the Black Country and 38 in the country, has acquired Stourbridge College's land and buildings on Hagley Road in Stourbridge.
And as it expands the school will allow secondary school-aged girls to attend for the first time since it was opened by local industrialist Thomas Foley in 1670.
Stourbridge College was closed by its financially-struggling operator Birmingham Metropolitan College (BMet) last summer, forcing students to travel to colleges in Dudley and Halesowen for further education.
The closure was met with major opposition by local residents and meant the college buildings were set to lie empty despite having had millions of pounds spent on them over the previous six years.
However after months of discussions the sale of the site to the Foundation of Thomas Foley, the charity that supports OSH, was agreed in October in a move welcomed by Dudley Council and West Midlands Mayor Andy Street.
It has now been confirmed that the school, which already allows girls to attend sixth form as day pupils, will admit girls from Year 7 for boarding or day learning from September 2021.
Headmaster Paul Kilbride said: “I am immensely proud and excited that our school will be able to offer to girls from near and far the same aspiration and opportunity that our boys currently enjoy.
"We know that we can make a difference to so many lives, not just through educational progress and achievement, but also through a full extra-curricular programme and a unique community based around the boarding environment.”
As a non-selective state boarding school, education is free but boarding must be paid for. Full board currently costs £12,180 a year and flexi-boarding costs £6,090 a year.
The only other nearby state boarding schools are the Royal School in Wolverhampton and Haberdashers' Adams grammar school in Newport, Shropshire.
Malcolm Wilcox, chairman of governors and feoffees, added: "The new facilities will benefit all members of the school community as they are opened.
"The space gained through the purchase of the site means that all pupils will be well placed to capitalise on the academic, sporting and extra-curricular opportunities that the future holds for all who attend OSH, and we are thrilled to be taking the school forward in such a positive direction."
The Stourbridge College site was originally owned by the Foundation of Thomas Foley but was sold off in the 1950s.
Registrations for September 2021 are now open.