International Airlines Group (IAG) will sell loss-making BMI Regional to Sector Aviation Holdings for £8 million ($12.9 million).
The two parties have signed a binding agreement, IAG confirms, which covers all fixed assets and long-term liabilities for the subsidiary, including its owned and leased aircraft.
Final approval of the transaction is required from the Civil Aviation Authority (CAA), but barring any opposition the transferral of ownership is expected to be completed within two weeks.
"This deal provides a future for BMI Regional and should secure around 330 jobs," comments IAG chief executive Willie Walsh.
IAG took ownership of BMI Regional and BMIbaby when it purchased BMI mainline from Lufthansa last month. The airline group originally intended to pay £172.5 million for the parent company, but subsequently agreed to also acquire its two loss-making subsidiaries for a "significant" discount.
BMI interim managing director Peter Simpson said last week that BMIbaby could be grounded as early as 10 September if a new buyer cannot be found.
Sector Aviation is a consortium of businessmen including the team previously known as Granite Aviation - the Loganair-linked group led by Ian Woodley.