The FLP is a new tool in the RBNZ's armoury to help the economy through the Covid crisis.
In their latest piece of analysis, ANZ economists, led by Sharon Zollner, suggest the FLP could be as large as $30 billion-$50 billion, and believe the Reserve Bank will go big to ensure the scheme succeeds.
The FLP will help mortgage rates go "meaningfully lower" in the months ahead, the economists said.
According to ANZ, FLP is the "next cab off the rank" as the central bank attempts to stimulate the economy.
The funding programme, which will lower borrowing costs for retail banks, is expected to be implemented by the end of the year.
It comes ahead of a potential move to a negative official cash rate next year.
A negative OCR is expected to further lower rates in the next 6-9 months, with mortgages tipped to drop to 1.5%.
The ANZ team say the FLP could take some of the short-term pressure off the Reserve Bank to lower the OCR.
Nonetheless, the team predict the OCR will fall, amid a "very challenging" outlook for the labour market and inflation in the wake of Covid-19.
"We still expect that the OCR will be dropped by 50bps in April, all things considered. But the introduction of the FLP tilts risks towards a lower or negative OCR occurring slightly later (say at the MPS in May) or more gradually (perhaps in 25bps increments, or with a cut to just above zero before deciding whether to take the OCR even lower)."