The Edinburgh-based charity, which manages 1,600 homes for disabled and elderly people across Scotland, employs 400 people and said the move to new premises would lead to the creation of more jobs.
Chief executive Fanchea Kelly said: “We always strive to be at the forefront of the latest innovations and technologies, and expanding in Dundee will allow us to continue to improve and enhance the lives of those we work with.
“It’s great to see the organisation come full circle, as the first Blackwood property was opened by the Queen Mother at Blackwood Court, Dundee in 1976.”
The charity currently has offices in Aberdeen, Edinburgh, Glasgow and Stirling. Its five-year business strategy has seen it set aside £13.9 million for housing investment, £2.3m for staffing needs and an extra £1.2m for care provision.
Earlier this year Blackwood secured a £5m funding package from ethical lender Triodos Bank.