An analysis undertaken by the Sunday Herald Sun has revealed that major banks of the country have raked a whopping $7 billion from borrowers over the past 2 years by rapidly hiking interest rates much more than the Reserve Bank's recommendation, and refusing to share official cuts in totality.

An average profit of $3000 has been made by banks from every mortgage holder who has taken a loan for buying of a new home. Credit card users have also been included in the list who found it difficult to pay back their dues in time during the global crisis, and had to deal with mounting interest rates.

By refusing to abide by the central bank's interest rate hikes and adding hikes of their own, all big Australian banks have increased the gap between cash rate and their own interest rates by almost 1%. The InfoChoice research has revealed the extra margin was costing borrowers "a $300,000 mortgage an average of $3129 a year in extra repayments".

"The total value of mortgages held by the big four banks as of October was $661.4 billion and given that more than 97 per cent of that is on variable rates, the extra margin that they have created by adding to the rate hikes and holding back on cuts equates to some $6.4 billion", said InfoChoice CEO Shaun Cornelius.

Authorities are now being urged to be more aggressive with the banks, and customers are being advised to shop around and find more reasonable banks to deal with.