First Westpac Bank raised interest rates, then it was Commonwealth Bank of Australia and today National Australia Bank has also announced a hike.
That's three of Australia's four largest banks, accounting for more than half of the Australian market.
National Australia Bank Friday increased home standard variable interest rates by 0.17 percentage points to 5.6 percent.
Commonwealth Bank on Thursday announced standard variable mortgage rates for owner-occupiers would increase by 0.15 percentage points to 5.6 per cent from November 20.
That followed Westpac's decision last week to raise its standard variable rate by 0.2 percentage points to 5.68 per cent, also from November 20.
The banks argue the increases have been spurred by new regulatory changes requiring banks to hold more capital against mortgages, to cushion for potential losses in the event that property prices dropped and the assets weren't worth as much.
Federal Treasurer Scott Morrison said it was up to each bank to respond to regulatory changes.
"Banks will make their own commercial decisions about how they charge customers in relation to shifts in their cost base," Morrison told media in Sydney.
"There's no mandatory requirement on behalf of the Government to pass on costs to consumers and different businesses will have different capabilities to do that and at the end of the day customers can choose where they want to bank and shop and buy their milk."
According to AAP, Commonwealth's changes mean owner occupiers with a $300,000 loan will fork out an extra $27 a month in repayments.
The fourth major Australian bank, ANZ, is not speculating whether it will follow suit.