New electronic ticketing cards used by Auckland public transport users will have to be replaced this year at a cost of more than $100,000.
Passengers swipe the pre-paid cards as they board and alight from public transport and are billed depending on the distance travelled.
The Hop cards were issued to passengers last year but are not compatible with new ticketing hardware being introduced on ferries, trains and some buses. At least 90,000 commuters use the cards.
By the end of the year the system will be rolled out to all modes of public transport, allowing passengers to change from ferry to train to bus on one ticket.
Auckland Transport says the cost of issuing new cards has been planned for and is included in the project's publicly funded $98 million budget.
It says the exact cost of replacing the cards is confidential, but is more than $100,000.
Holders of current Hop cards will be able to swap to the newer version for free.
The Campaign for Better Transport says customers will have assumed they could use last year's card into the future and will question how well the rollout of the system is going.