Hundreds of thousands of customers of popular electronics retailer The Good Guys have been warned of a potential data breach.

The apparent data theft related to customers who had signed up for the company’s rewards program.

The Good Guys said it had contacted 325,000 members of the rewards program who had set up a My Rewards account.

Another 1.5 million customers may also have had their personal details impacted and have also been made aware.

The company said the breach related to people’s names, addresses and phone numbers.

The information may have been accessed when the IT systems of a former third-party provider — My Rewards Pty Ltd — were accessed by an “unauthorised user”.

The Good Guys said its own systems had not been hacked and it no longer used that provider.

The beach follows high-profile hacks at Optus and Medibank that impacted millions of Australians last year.

In a statement on Thursday, the Good Guys said the breach happened in 2021 but it had only now been made aware.

“The Good Guys is directly contacting Concierge members who may have been impacted by the My Rewards data breach,” the statement said.

“The nature of the specific information involved for each affected individual is set out in the communication that the individual receives from The Good Guys.

“The Good Guys is extremely disappointed that My Rewards, a former services provider, has experienced this breach and we apologise for any concern that this may cause.”