The Edinburgh hotel - owned by the Royal College of Surgeons of Edinburgh - will go from 77 rooms to 129.
Run by the college's commercial arm, Ten Hill Place will receive an £8.5m injection to expand from 77 to 129 rooms. Capacity of the restaurant and wine bar will also be increased, and a gym will be added.
Profits generated by the hotel are invested by RCSEd into improving surgical standards for patients around the world, including those in areas of conflict and extreme poverty. In its last financial year, Ten Hill Place posted record turnover of £2.69m on the back of an 88 per cent occupancy rate.
“As the number of visitors to Edinburgh has soared, we have been able to tap into the market and develop our reputation – meaning that the hotel is now busy all year round,” said Scott Mitchell, commercial director of RCSEd.
“Having initially targeted visiting academics, medical professionals and delegates to conferences, our customer base is now especially varied – especially during festival season and Hogmanay.”