The Commonwealth Bank is tightening the reins on its home-loan book to comply with the Australian Prudential Regulatory Authority's loan-growth rules.
CBA has lifted interest rates on its interest-only home loans by 12 basis points to 5.68 per cent.
The bank said the change was made with the aim of "meeting its regulatory requirements".
In 2014, the Australian Prudential Regulatory Authority said banks that saw more than 10 per cent annual growth in their investor mortgage book would be penalised.
The higher rate will come into effect on 3 April. Customers can switch to principal plus interest loans for no charge to avoid the higher rates.
The rate rise follows the announcement earlier in the week that CBA subsidiary BankWest will exclude the benefits of negative gearing from loan applications.
CBA posted a better-than-expected first-half profit of $4.9 billion this morning, a result driven by 7.7 per cent growth in its home lending book.
To read more about CBA's first-half result click here.
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