Auckland Transport will offer free reloadable Hop cards for travel on trains and ferries to registered holders of the existing buses-only version.
Chief operations officer Greg Edmonds says existing cardholders will be able to apply online at AT.co.nz from later this week.
Others will be offered an early-bird discount price of $5 for new Hop cards next week, rising to $10 once they are introduced to trains on Saturday, October 27, with ferries to follow on November 30.
Mr Edmonds' advice comes after public confusion over whether existing cardholders may have to pay a second time, as a result of an inability to incorporate both Hop versions into the one transport network.
The complication comes after a decision by Auckland Transport in August to dump Wellington-based Snapper Services - which supplied the original cards to its sister company NZ Bus - from third-party involvement in the $110 million Hop project.
It alleges Snapper failed to meet a Government-approved national standard, although the card company denies missing any deadlines and says it will claim $10 million to $20 million in costs from Auckland Transport.