Commonwealth Bank of Australia (CBA) issued its "sincerest apologies" to customers on Thursday afternoon, notifying them that its systems are experiencing network issues.
"We are experiencing an issue with our network this afternoon that is affecting banking services," the bank wrote in an email to customers.
"We are very sorry for the inconvenience this is causing you."
The bank confirmed network issues have resulted in BPAY services, including PayID payments and cardless cash, being made unavailable, as well as some in-branch services, call centre services, CommBiz log on, and some CommBiz payments.
In addition, the bank said some debit card payments may be affected, while the CommBank app and Netbank is still available, but with limited functionality.
A small number of branches have also closed as a result of the network issue, the bank said.
The bank added it is "working urgently to fix the problem and will have services restored as soon as possible" and will keep customers updated with regular posts on its website and via its social media pages.
The hiccup comes a day after the bank claimed it would spend over AU$5 billion on technology in the next five years in a bid to improve its systems and services.
As part of the bank's 2019 annual general meeting, CBA CEO Matt Comyn said as customers increasingly choose to interact with CBA online, being the "best in digital" will continue to be a key part of the bank's strategy.
"With 7 million active digital customers and 7.4 million logons per day, we're doing all we can to make banking more personalised and more convenient," he said.
For the 2019 financial year, Commonwealth Bank reported AU$8.6 billion in statutory net profit after tax, slipping 8.1% from the AU$9.3 billion that was recorded a year prior.
Operating expenses increased slightly for the bank by 2.5% to $11 billion. Of that amount, AU$1.9 billion was spent on information technology services, 8% more than FY18, primarily due to increased IT infrastructure costs, risk and compliance spend, and software license costs.
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