Bristol's M Shed has been awarded a £1.39m grant by the Heritage Lottery Fund in order to cover 'unforeseen costs' incurred as part of the £26.6m museum development.
The funding will also be used towards fundraising targets and the completion of a learning studio at the new attraction, which is due to open on 17 June.
M Shed, which has been built by BAM Construction, has already received £10.2m from the HLF and will house working exhibitions such as historic boats, trains and cranes.
Learning spaces; a café; a book and gift shop; and a workshop and train shed will also form part of the M Shed's offer, along with and function areas.
Julie Finch, head of Bristol's museums and archives, said: "The HLF decision recognises the difficulties we have had with a number of unforeseen elements associated with the major challenge of restoring a 1950's harbourside, transit shed and transforming it into a 21st century state-of-the-art museum.
"The additional funding added to the ongoing support for staffing costs from DCMS will enable us to fully realise our ambitions for the museum in time for opening."