The government is installing new ‘‘Opal-only’’ ticket barriers at several Sydney stations and the old gates will be removed and installed at gateless stations.

Six of the new barriers have been installed at Bankstown and will be trialled for a month.

After that, the barriers will also be installed at Parramatta, Central, Town Hall and Wynyard by early next year.

The old gates from these stations will be reinstalled elsewhere.

The Illawarra, which has few if any gated stations, could end up with some of these gates at key stations.

Transport for NSW is evaluating which ungated stations will receive these paper ticket gates, based on patronage and station design.

A spokesman said further announcements on the selected stations will be made once the evaluation is complete.

The new Opal-only barriers come with higher gate paddles that are designed to make it difficult for people to jump over them.

The barriers also make it much more difficult to tailgate, where two people pass through the gate at once.

“Customers who pay their way expect others to do the same,’’ Transport Minister Andrew Constance said. ‘‘This is another way to deter the dodgers who are taking everyone else for a ride.’’

For those commuters obeying the rules, the new barriers process data more quickly so people can tap on and off faster. 

The aisles are wider and the larger screens easier to read and extra sensors reduce the risk of the gates closing while customers are passing through.