Auckland Transport said rail tickets and AT Hop cards would be accepted on all scheduled buses. However, passengers were being encouraged to find alternative transport.
Auckland Transport spokesman Mark Hannan said no extra buses were operating as a result of the train fault.
Train driver just told Newmarket passengers to get off at Grafton, then went to Newmarket anyway. Psych! @AklTransport
Passengers contacting the Herald this morning reported bus shuttle services were full and many people were still waiting to get on a bus in to downtown Auckland.
"I was affected coming in from the Western Line,'' Louise King said.
"Had a train person come along and tell us that we had stopped at Morningside station and could get off to wait for a Rail bus. Managed to get on another bus service but it was jammed packed - so many people not knowing what to do or where to go, looking very lost,'' she said.
Another passenger was on a train that got stuck at the Kingsland station.
She said about 50 people got off the train and had been waiting for a bus since before 8am.
"All buses going past are already full,'' she said.