The length of time Sydney homeowners have to wait for development applications to be assessed has fallen by weeks in many areas where councils have installed the NSW government's online system for lodgements.

Following a trial over the past year, the government plans to require 42 local councils in Sydney, Illawarra, Newcastle and the Central Coast in 2020 to roll out the ePlanning tool.

The technology allows homeowners and developers to lodge their application online, instead of providing paper documents to councils.

The online portal has helped cut assessment times for development applications. Credit:James Alcock

It also means the public can view a development application less than a day after it is lodged with a council, instead of having to wait six to 18 months.