Many Australians risk losing their phone and internet access in 2017, with their home services cut off if they fail to switch to the National Broadband Network service available in their area.

After getting off to a slow start, the NBN rollout has reached 3.5 million premises across the country. While the network initially planned to run fibre to the premises at 93 per cent of homes and businesses, the new-look multi-technology mix will see the lion's share of premises rely on potentially slower fibre to the node connections. Telstra's metro-centric HFC cable broadband network will also be retained as part of the NBN, but not the Optus cable network.

While 3.5 million Australian homes and businesses can now activate an NBN-based broadband service, to date only 44 per cent have made the switch — the rest sticking with older copper and cable-based phone and internet services even though the clock is ticking.

Homes and business have 18 months to migrate to the NBN once it is available to them, after which traditional copper and cable services in the area are severed — cutting off fixed-line phone and internet access.