The value of mortgages on floating, as opposed to fixed, rates looks set to reach its highest level since Reserve Bank records began.

Reserve Bank data shows as of September 40.3 per cent, or NZ$66.9 billion worth, of mortgages were floating.

That's the first time the per centage of floating mortgages has been over 40 per cent since October 2002.

The highest rate on record is 43.1 per cent in January 2000.

The Reserve Bank records go back to June 1998.

September was also the first time the value of fixed term mortgages has fallen under NZ$100 billion since June 2006, coming in at NZ$99.2 billion.

And of the fixed mortgage total, NZ$53.6 billion worth, or 54 per cent, had less than a year to run suggesting a continued rise in the number of borrowers shifting to cheaper floating rates with the Reserve Bank not expected to hike the Official Cash Rate from 3 per cent until March next year.

The major banks are currently advertising floating mortgages rates priced from 6.09 per cent.

The lowest one-year fixed rate on offer is 6.45 per cent and lowest two-year 6.68 per cent. Six month fixed rates start at 6.25 per cent.

These figures exclude HSBC which advertises a 6.05 per cent floating rate, 5.49 per cent six month fixed rate, 5.99 per cent one year rate and 6.49 per cent two year rate.

However, the catch to HSBC's low rates is customers' must have mortgages worth NZ$500,000 or savings of NZ$100,000 to qualify for a loan.

ANZ, the country's biggest bank, said in its annual results last week that fixed rate loans now comprise 63 per cent of its mortgage book versus 88 per cent two years ago.

And as ANZ's economists put it this week, with about 72 per cent of total mortgage debt of NZ$166.8 billion at maturities of one year or less, the Reserve Bank currently has "considerable" monetary policy traction.