Half of these premises are connected using either fibre-to-the-node (FttN) or hybrid fibre coaxial (HFC) cable.
The company said in a media release that the rollout had been sped up, with an average of 250,000 premises made serviceable each month this year up to March.
It said that from April to June, a further million premises would be added, to meet its target of making 5.4 million premises serviceable.
NBN Co chief network engineering officer Peter Ryan said the company was proud to reach what he described as yet another key milestone and attributed it to the "outstanding work and pace set by the team at NBN Co and our delivery partners".
“NBN Co continues to demonstrate its rollout momentum with 140,000 services made available to homes and businesses across the country in a single week – the equivalent of lighting up Canberra - with five million homes and businesses in total now able to connect to retail services over the NBN network," he said.
"We are building the NBN network and activating end users faster than we have ever done before and are currently making over 60,000 premises serviceable each week.
“We have the flexibility and the right technologies in place to design and build the network at the speed and scale needed to reach our end goal by 2020.”