The V&A in Dundee plan has already raised £15m from the Scottish Government, with a further £9.2m from the Heritage Lottery Fund, but the private donations represent a "major step" towards the full cost of the project, its organisers said, as a redesigned version of the museum is unveiled.
Sandy Richardson, development director of V&A at Dundee, said: "The private donations announced today mean the project is well on its way to achieving the £45m fundraising target.
"We are absolutely delighted to be able to make this announcement and are extremely grateful to those individuals and organisations who are supporting the project."
Among those who have donated are WS Philips Charitable Trust, Leng Charitable Trust, Misses Barrie Charitable Trust, Binks Trust, and the Dunard Fund, while some donors have chosen to remain anonymous.
News of the funding comes as the project displays its latest building plans as part of a new exhibition open to the public at Bernard King Library at the University of Abertay.
Architect Kengo Kuma's revised plans show V&A at Dundee moving shorewards – closer to the RSS Discovery and Dundee's redeveloped central waterfront.
The revised planning application will be lodged with Dundee City Council later this year following the 12-week public consultation period.
V&A at Dundee will be the first-ever purpose-built design museum to be constructed in the UK outside London.
It will provide more than 1700 sq m of gallery space.