HSBC systems, including cashpoints and internet banking, appear to have gone down.
Customers from across the world have complained about being unable to withdraw money or use internet banking.
"Disappointed with #HSBC how can their system be dwn. Haven't been able to buy or take out any money for an hour," said Twitter user MissYummyMama.
"#hsbc bank down, cant log-in to internet banking, can't draw money out & can't use card," said mattwing79.
Our sister title Cloud Pro has been attempting to use both the HSBC phone and internet banking services but could not access either.
The HSBC website is up yet it appears to be impossible to login.
"I'm sorry this service is not available right now," an automated message on the phone service said.
HSBC confirmed it has heard of some issues and is investigating.
"We are aware of some problems and are looking into them as a matter of priority. Follow this account for updates when they are available," the bank tweeted.
"Sorry for the inconvenience."
First Direct, a division of HSBC, is also down, according to reports.
There have been murmurings of the Occupy movement being responsible for a hit, although it is only because of the following link: http://occupytheurl.com/?url=www.hsbc.com.
HSBC has been hit with a number of tech failures in the past. Last year, a mainframe issue left many unable to access their funds.
