ATHENS (Reuters) - Greece's second-largest bank Piraeus (>> Piraeus Bank SA) said about 12 percent of its workforce signed up for a voluntary redundancy scheme aimed at cutting costs after recent acquisitions.

The bank had an initial target of 10 percent.

Greece's top four banks are updating their restructuring plans after their recapitalisation in June, aiming to squeeze their costs even further.

Piraeus, which employs about 18,000 people, bought smaller lender Geniki from Societe Generale (>> SOCIETE GENERALE) last year and the healthy part of ailing state lender ATEbank.

It acquired the Greek branches of Cypriot lenders Bank of Cyprus (>> Bank of Cyprus Public Company Ltd), Cyprus Popular (>> Cyprus Popular Bank Public Co Ltd) and Hellenic Bank (>> Hellenic Bank Public Company Ltd) earlier this year to shield the country from the island's crisis.

The group also bought the Greek unit of Portugal's Millennium BCP (>> B. COM. PORTUGUES), concluding its acquisitions drive.

Piraeus, Alpha (>> Alpha Bank S.A.), National (>> National Bank of Greece) and Eurobank (>> Eurobank Ergasias SA) - completed a 27.5 billion euro recapitalisation in June to restore their solvency after losses from writedowns on government debt and bad loans.

(Reporting by George Georgiopoulos; Editing by Louise Heavens)