Heartland New Zealand says a decision on its application for a banking licence is expected by November.
It says the Reserve Bank has confirmed that the formal determination process has now begun and the process is expected to take several months.
Heartland says the timing of the process remains uncertain and the outcome remains unknown.
If the Reserve Bank declines the application there is no appeal process, though the building society can apply again.
Meanwhile, Heartland will publish its full-year results on 28 August.