PayPay Securities Halts All Japanese Stock and ETF Trading After Mizuho System Failure

Summary

PayPay Securities has suspended trading in all Japanese stocks and ETFs. The disruption was triggered by a system failure at Mizuho Securities, its external order-processing partner. The companies say the issue was not caused by a cyberattack or unauthorized access. Advance orders for transactions from the 14th onward are also temporarily unavailable. Customers can still trade U.S. stocks and check their asset information. PayPay Securities is working to restore Japanese-market trading by the opening of trading on the 14th. An update on the recovery outlook is expected around 8 a.m. Read the full article for details on the disruption and what investors should watch next.

PayPay Securities Halts All Japanese Stock and ETF Trading After Mizuho System Failure

PayPay Securities suspends trading across Japanese stocks and ETFs

PayPay Securities has suspended trading in all Japanese stocks and exchange-traded funds, or ETFs, following a system failure at Mizuho Securities, the external partner responsible for handling orders. The disruption affects every Japanese stock and ETF available through PayPay Securities, preventing customers from placing trades while the problem is being resolved.

The online brokerage said it has also stopped accepting advance orders for transactions scheduled from the 14th onward. The company is working to restore services in time for the opening of market trading on the 14th and expects to provide an update on the prospects for resuming transactions at around 8 a.m. that morning.

U.S. stock trading and account access remain available

While Japanese stock and ETF transactions are unavailable, customers can continue trading U.S. stocks through PayPay Securities. Users can also check their asset balances and account information, according to the company. This means the disruption is currently focused on Japanese-market trading functions and does not represent a complete shutdown of the platform.

PayPay Securities said the incident was caused by a system problem at an external connection point, Mizuho Securities, which is entrusted with processing orders. The cause of the failure has been identified, and the company stated that there is no indication that the incident was caused by a cyberattack or unauthorized access.

Mizuho Securities reports related disruption

Mizuho Securities separately announced on the 13th that it had partially suspended the acceptance of Japanese stock orders for institutional investors because of a system failure. The company apologized for the inconvenience and disruption caused to its customers.

The two announcements highlight the important role that connections between online brokerages and established securities firms play in Japan’s financial markets. Although investors often place orders through a smartphone application or web platform, the actual routing, execution, settlement and market-related processing may depend on several linked systems operated by different financial institutions.

What investors should know

Customers affected by the PayPay Securities suspension should check official announcements before attempting to place or modify Japanese stock and ETF orders. Investors should also be aware that market conditions can change while trading is unavailable, potentially affecting prices when service resumes. Any pending or scheduled orders should be reviewed carefully once the company confirms that normal operations have returned.

PayPay Securities expressed its deep apology for the significant inconvenience caused to customers and said recovery work was continuing. The company’s next important update is expected around 8 a.m. on the 14th, ahead of the planned reopening of trading. Until then, Japanese stock and ETF transactions remain suspended, while U.S. stock trading and asset-status checks are expected to remain accessible.