The cardboard tickets used for Adelaide public transport will become invalid from the end of this month

The South Australian Government said Crouzet multitrip tickets had not been sold since the middle of the year.

Transport Minister Stephen Mullighan said that any time until the end of next February, commuters could transfer the dollar value of unused trips from their old multitrip tickets to a plastic Metrocard, or get single trip tickets in exchange.

He said since MetroCard was introduced there also were cheaper trip options for Adelaide commuters, such as a 28-day pass which allowed unlimited travel in that period.

To transfer the remainder of multitrip tickets to a Metrocard, commuters can go to Adelaide railway station in the city or the Metro InfoCentre at the corner of Currie and King William Streets.

Another option is to post the multitrip tickets to Reply paid 83100 GPO Box 1533, Adelaide 5000 and enclose a return address, so single trip tickets can be posted out.

Mr Mullighan said the plastic smartcard now accounted for 86 per cent of trips taken