UPDATE 1-Italy antitrust probes banks on overdraft charges

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ROME, July 18 (Reuters) - Italy's antitrust watchdog has opened probes into the way some of Italy's biggest banks calculate charges for exceeding overdraft limits, the agency said on Friday.

The banks being investigated are BNL, a subsidiary of France's BNP Paribas (BNPP.PA), Intesa Sanpaolo (ISP.MI), Banca Monte dei Paschi di Siena (BMPS.MI) and UniCredit Banca di Roma (CRDI.MI), the watchdog said in a statement.

The agency will investigate "whether consumers were informed, clearly and comprehensively, on the way overdraft charges are calculated and what they are," the agency said.

Intesa Sanpaolo is the country's biggest retail bank and UniCredit is the largest by market capitalisation -- and one of Europe's top five lenders.

The conservative lending policy of Italian banks, combined with a relatively wide spread between savings and loan rates, have helped them weather the global credit crunch better than European and U.S. lenders.

But they have also found themselves under scrutiny from regulators attempting to ease financial pain for ordinary Italians.

The antitrust agency is also investigating 10 banks -- including the four in this probe -- over incorrect practices in the transfer of mortgages. (Editing by David Cowell)