A survey has found more than one in three Australians have no plans to switch to the NBN or don't actually know what it is, apparently unaware that once the new network arrives their existing phone and internet connections will be switched off.

The NBN has started running television advertisements to remind Australians to switch to the new broadband network — and the latest survey results from comparison site Finder.com.au seem to justify the expense of the public awareness campaign.

When asked how fast they plan to connect to the NBN once it becomes available for their home, 17 per cent of 2004 people said they would not make the switch at all. A further 18 per cent didn't know what they would do or didn't understand what the NBN was about.

Even among those that planned to switch, 2 per cent said they planned to switch between 18 and 24 months after it arrived in their area, which would also leave those people in the dark as telcos are obliged to deactivate existing copper lines within 18 months of NBN availability. Adam Turner

Even among those that planned to switch, 2 per cent said they planned to switch between 18 and 24 months after it arrived in their area, which would also leave those people in the dark as telcos are obliged to deactivate existing copper lines within 18 months of NBN availability.

The total of 37 per cent that would be left in the dark, according to Finder.com.au, is equivalent to 6.6 million Australians. Finder tech spokesperson Alex Kidman expressed surprise that so many people still think the NBN is optional.