The Commonwealth Bank says it is fixing a technical issue that has taken down several systems including ATMs, mobile banking apps and online share trading platform CommSec.
"The Commonwealth Bank is currently experiencing system problems," a representative said.
"We have identified the issue and we are working to restore services as a priority. We apologise for any inconvenience caused."
Several services including Commbank and MyWealth crashed on Tuesday morning and wouldn't allow users to log in.
ATMs and EFTPOS were also reportedly effected.
Customer complaints began to appear on social media shortly before 8am (AEST).
