Australia's Federal Court ruled on Friday that Telstra (ASX:TLS) misled nearly 9,000 customers by failing to disclose a reduction in their broadband upload speeds, following legal action by the regulator, the Australian Competition and Consumer Commission (ACCC) said in a Friday statement.

In October and November 2020, Telstra migrated 8,897 customers who were on a Belong National Broadband Network plan with a maximum upload speed of 40 megabits per second, to a service with a maximum upload speed of 20Mbps, the regulator added.

"There was no reduction to the price Telstra charged its customers even though the cost charged by NBN Co to Telstra was AU$7 a month less for the new, lower speed service.", said ACCC Commissioner Liza Carver.

Telstra admitted to telling 2,785 customers that they were receiving a maximum upload speed of 40Mbps when they were not, the statement added.

The telecommunications firm acknowledged its failure to disclose the migration to its customers in 2021 and provided a one-off AU$90 credit to the affected consumers.

The ACCC said it is seeking declarations, penalties, consumer redress, costs, and other orders and the court will determine the penalty and any consumer redress after a hearing on a date to be fixed.

Telstra has previously paid AU$15 million in penalties after being found guilty of making misleading promotions about internet speed plans in 2021.

Telstra did not immediately respond to a request for comment from MT Newswires.