Mizuho to halt ATM, online banking services over three-day weekend


Mizuho Financial Group Inc., the parent of Mizuho Bank, will temporarily suspend ATM and online banking operations over the three-day weekend starting Saturday to conduct data transfers.

Services will be suspended from midnight Friday to 8 a.m. Tuesday to allow the group to conduct the second round of data transfers, part of its attempt to unify its core computing systems for banking.

Mizuho Financial has an enormous amount of customer data, with about 24 million customers in its retail banking operations alone.

The group plans to conduct nine rounds of data transfers over a yearlong period to securely complete the process after its banking unit experienced two massive system failures years ago.

The first round was completed on June 11 without any hitches, but a glitch occurred later that month in a securities trading system separate from its banking operations.