It is understood further bills in the region of £1 million could be on their way, including an invoice from contractor Nuttall for its work on the doomed Snøhetta and Spence Associates project.
The amount of wasted cash spent on the failed gallery - dropped last month after seven-fold budget increases - has now reached the £7 million mark.
Nuttall was appointed to build the £50 million gallery in the summer, but the final contract between the firm and KCC was never signed.
A council source told the Thanet Gazettethe agreement was due to be sealed last October but was 'staved off' to keep down the costs of breaking the contract.
Project boss at KCC Mike Hill said: 'We have paid so much so far and we still have to finish payment of our contract. Edmund Nuttall has to be paid for the work it has done.
'There are also bills for other work which has gone on, so it will be something in that order.'
Hill continued: 'Of the money spent, a lot of it is still going forward.
'This is work that will be required for the new project. We are not starting with a blank sheet of paper.
'My job now is to build the art gallery.'
A design brief for the new gallery - which will be constructed on land - is currently being drawn up by the council.