Yorkshire-based company Stadium Group plans to take over the Kent amusment park and turn it into a retail and leisure complex.
Present owner Jim Godden has confirmed Dreamland will stay open until September but then it will be used for other leisure activities.
Thanet District Council has pledged to give economic support the town to the town when the amusement park closes.
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One-fifth of the visitors that come here name Dreamland as their reason for coming
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Iris Johnstone, Thanet Council
Speaking on BBC Radio Kent, Iris Johnstone, Thanet Council's deputy leader and tourism chief, said: "We must have a major attraction, perhaps even an all year round covered attraction, for people to continue to come to the area.
"One-fifth of the visitors that come name Dreamland as the reason for coming particularly the day-trippers."
The park has been going for 84 years and one of its most famous rides, the Scenic Railway, was granted listed building status in 1991.
Mr Godden, who also owns the Rotunda Park in Folkestone, part of which has been demolished to make way for flats and shops, said Dreamland was too large for Margate.