But the latest Australian Competition and Consumer Commission data released on Tuesday also shows download speeds have withstood COVID-19 pressure on home connections through successive lockdowns.

"There is a persistent cohort of fibre-to-the-node customers that are still experiencing slower than expected speeds, and NBN Co and retailers have been slow to address this," ACCC Commissioner Anna Brakey said.

"Retailers and NBN Co need to collectively do more."

The proportion of underperforming services had more than halved in the past three years, to 6.2 per cent in May 2021.

Broadband consumers on fixed-line NBN connections are experiencing record high speeds.

Most consumers received their maximum plan speeds more often in the peak evening hours of 7pm to 11pm.

The watchdog also tracked a "sustained performance increase" in download speed, despite pressure on home connections through lockdowns, measuring from before the pandemic in February 2020 through to July 2021.

From July 2020, broadband speeds picked up significantly, after NBN began "over-provisioning" with a speed boost on most of its products.

But the latest Measuring Broadband Australia report found fibre-to-the-node connections are still not performing as well as other network connections.

The report shows consumers on 50Mbps and 100Mbps fibre-to-the-node plans received lower speeds than the maximum plan speeds at any given time.

For the first time, the report includes video streaming results for the NBN Fixed Wireless Plus plan to better reflect how Australians use the internet.

The results show that most households on the plan can support five simultaneous high definition streams from Netflix, or one ultra-high definition video stream.

Ms Brakey encouraged consumers on very high-speed plans to contact their service providers to check their equipment could support their plan, and called for retailers to help people sign up for a suitable deal.

Dodo and iPrimus posted the largest improvement of the telcos over the quarter, after the Federal Court found they needed to improve their speed testing.

Vodafone and MyRepublic also improved their speeds in peak hours.

Australian Associated Press