The average cost of a cyber attack has also hit $276,000 and has become one of the biggest concerns for local companies, a Business SA report has found.

Crime Stoppers communications and engagement director Adam Thomson said cyber criminals targeted all Australian states and territories equally.

"Some criminal enterprises operate their own call centres and there are incidents where criminals intercept legitimate invoices between a supplier and customer, change the bank details, then forward it back on to the customer for payment" Mr Thomson said.

"(Cyber) criminals are not fussy who they target, so any industry or business with an online presence or that uses common online platforms is susceptible."

The Business SA report found more than two-thirds of South Australian companies were victims of cybercrime in the past two years.

Mr Thomson said it was likely even more had been hit, with many not wanting to admit being targeted.

He said ransomware attacks, where computers were remotely locked and a payment demanded to allow access, were also becoming increasingly common.

Business SA chief executive Martin Haese said as more businesses moved to an online platform, so too had the number of attacks increased.

"It demonstrates businesses need to be on the front foot to get themselves prepared," Mr Haese said.

"We've seen cost impacts of $10,000, which for a small business can be significant, but that goes right up to $1.3 million."

Australian Associated Press