Tasmanian-based lender Bank of us will keep 40 per cent of the latest interest rate cut.
Bank of us on Tuesday said it would pass on a cut of 0.15 percentage points to people with variable home loans and residential investment loans.
That followed the Reserve Bank last week cutting the cash rate by 0.25 percentage points to a record low 0.75 per cent as part of its continued bid to stimulate the economy.
Bank of us passed on 0.15 percentage points from each of the 0.25 percentage point cuts by the Reserve announced in June and July.
Tuesday's announcement meant it would pass on 0.45 percentage points of a potential 0.75 percentage points since the June cash rate cut.
Another Tasmanian-based lender, MyState Bank, announced cuts of 0.20, 0.20 and 0.15 percentage points in that order following the Reserve Bank's three recent cash rate cuts.
The big four banks have also been holding back chunks of the cash rate cuts.
They announced they would pass on amounts between 0.13 and 0.15 percentage points of the most recent cut.
Bank of us chief executive Paul Ranson on Tuesday said the bank understood some customers had an expectation the full amount of the cash rate reduction would flow to lending interest rates.
"However, the cash rate is only one of the many factors we have to consider when making a change to interest rates," he said.
"Fortunately, we don't have to maximise our profits for shareholders, but in this low interest rate environment, we must balance both our borrowers' and depositors' expectations, and make sure that our business remains sustainable for the long term."
He said the bank's rates remained among the most competitive in the market.
"Our FlexiDiscount home loan limited time special remains competitive in the market at 3.18 per cent per annum for lending up to 90 per cent loan to value ratio," he said.
He said the revised rates for existing loans would apply from November 1.