Tickets for the Toll Stadium gig were originally $85.50.
Yesterday morning, two Trade Me auctions for double passes to the concert had sold for $300 and $310.50. A similar auction in the afternoon netted $270 for two tickets and another was poised at $250 overnight.
On Thursday, controversial online site Viagogo - which fans have been told to avoid after void tickets emerged - were selling six tickets ranging from $139 to $151 each.
By Friday morning they were sold.
The Trade Me sellers professed to be unable to attend the concert after personal circumstances had changed.
One seller was successful with a $300 "buy now" auction for two tickets, despite a fellow Trade Me member pointing out the original $85.50 single ticket price.
The seller replied that they had bought the tickets "second hand for $300, but (I) was gifted tickets so now selling at the price I bought them".
The crowd capacity for Six60 is 10,000, which might seem small for a stadium that can hold more than double that for sporting events.
However, concerts require a stationary stage set-up which alters the crowd capacity.
The capacity for tonight has also been increased since January 2016, when the band played at Toll Stadium to about 4000 people in wet weather.
Interest in the Whangarei concert is buoyed by it being the band's last headlining performance of its summer tour.
They will support Ed Sheeran for three concerts in their hometown Dunedin next weekend.
About 40 per cent of the 10,000 ticket sales are from outside Northland.