The National Broadband Network is expected to help create more than 5500 businesses and tens of thousands of jobs in South Australia by 2021.

Research commissioned by NBN Co shows the growth of businesses in SA connected to the network in 2017 grew at twice the pace of the national average, with 230 new companies created.

“We’re already seeing promising examples of highly-connected areas, such as Mount Gambier in the southeast, counter industry downturns by creating online start-ups to reach overseas markets,” NBN Co chief Bill Morrow said on Thursday.

NBN Co now believes up to 35,700 digital jobs, including software programmers and graphic designers, will be created in the state by 2021 as a result of access to fast broadband.

“The NBN access network will provide the digital backbone for businesses in South Australia and has the potential to change the very nature of local towns and regions,” Mr Morrow said.

The broadband network is also expected to rapidly boost self-employment in the state, with more than 6500 additional people expected to be self-employed by 2021.

Currently, 542,000 South Australian homes and businesses have access to the NBN with the rollout expected to be completed by 2020.