Rail services between the Auckland suburbs of Swanson and Waitakere are to be scrapped.
They'll be replaced with buses once Auckland's new electric trains are operating on the Western Line in 2015.
Auckland Transport's Mark Lambert says the line is only electrified to Swanson and there's no money to extend it through the Waitakere tunnel.
"Given the relatively low numbers of people using the services at the moment and also the cost difference between train operations with diesel and bus services we've concluded that bus services are actually the best solution moving forward."
Mr Lambert says it's more cost effective to use buses because operating a diesel train on that section of the line would cost $1.5 million a year, that's compared with $285,000 to operate buses.
Mr Lambert says only around 100 people use the service at the moment.