Consumer advocacy group Choice is demanding customers be allowed to break their fixed contracts if they have been affected by Telstra's multiple phone and internet network outages.

Spokesman Tom Godfrey said an analysis of 280 telecommunications plans revealed some Telstra customers were paying up to 92 per cent more than other consumers for their home broadband internet and up to 35 per cent more for their mobile plan.

However, he said the network has experienced seven major outages over the past six months and customers should be allowed to break fixed contracts if they were unhappy.

"There's only so much free data Telstra can offer before they have to admit that their network is failing on a fairly regular basis and that promised premium network is a thing of the past," he said.

"Telstra should do the right thing and let those seeking to get out of a fixed term contract do so.

"Telstra claims its real point of difference isn't data limits or cost but its network. Log those outages, record your loss and then if Telstra doesn't agree to let you out take the fight to the TIO because they're clearly charging you a premium price and you're not getting a premium service."

In June an outage impacted up to 75,000 Telstra customers around Australia — the latest in a series of network failures.

In May, Telstra announced it would be giving customers who were "offline for an extended period" $25 credit and an apology.

The company acknowledged that outage alone had affected 10 per cent of their internet customers — roughly 370,000 people.

Telstra has previously offered two free data days to compensate users for network failures and announced it would spend an additional $50 million on its mobile network in a bid to prevent ongoing outages.

However, Mr Godfrey said investing millions into its failing network was "too little too late" for consumers.