The Bank of Italy estimated on Thursday the total cost for the state rescue of Banca Monte dei Paschi di Siena would be about 6.6 billion euros ($6.92 billion), a statement said.
The immediate costs for the state will be about 4.6 billion euros, while an additional 2 billion euros will be needed later to compensate retail investors.
The costs for "other entities" will total about 2.2 billion euros, the central bank said.
Monte dei Paschi, Italy's third biggest lender and the world's oldest, said on Monday the European Central Bank had estimated its capital shortfall at 8.8 billion euros, compared with a 5 billion euro gap previously indicated by the bank.