Brighton's run-down Saltdean Lido has been given a grant of almost £440,000 towards its renovation.
The owners said it hoped to reopen the pool next June after being awarded the funding from the Social Investment Business (SIB).
The Saltdean Lido Community Interest Company (CIC) has been granted a 60-year lease to operate the pool by Brighton and Hove City Council.
The 1930s art deco structure is the UK's only Grade II*-listed lido.
The lido is to be restored by Sir Terence Conran's design firm after it won a competitive tender in which a number of companies submitted proposals.
The grant of £439,800 will be used to restore the main swimming pool, install a new plant room, landscape the grounds and for temporary changing rooms and toilets.
The owners have already submitted a planning application to Brighton and Hove City Council for permission to renovate the site.
They expect about 300,000 people will use the lido next summer after completion of phase one of the £5m project.
The CIC has also submitted a bid to the Heritage Lottery Fund for £4.9m with a decision expected in January.
Rebecca Crook, director and chair of Saltdean Lido CIC, said: "This is a monumental step in us achieving our vision of restoring the entire site and bringing it back into full use for the benefit of local residents and visitors alike."
Plans announced in 2010 to partially demolish the 1930s Grade II* listed complex and build flats were rejected.
The lido has been closed for several years and the buildings remain on the English Heritage At Risk register.