Home loan borrowers may not be happy with the major banks' decision not to pass the rate cut in full, but self-managed superannuation investors are having a field day as they welcome the increase to rates on deposit accounts.

Investment advisers also backed the banks' decision, saying that the banks—in the face of greater capital requirements and higher funding costs—have a duty to act in the interest of their shareholders.

"Banks are owned by shareholders. They answer to shareholders, so you can expect them to look after shareholders," said Sam Henderson of advice firm Henderson Maxwell.

The SMSF Owners' Alliance also argued that the primary responsibility of banks lie on their depositors, not their borrowers.

"Banks have such a central role in the economy as facilitators of commerce, providers of loan funds for investment, and as safe houses for savings, so it is axiomatic they need to be financially strong, well-managed, and closely supervised," said SMSF Owner's Alliance chief Duncan Fairweather. "The global financial crisis showed how important it is for national economies to have strong banks."

Though the major banks passed no more than half of the 25-basis-point cut to its customers, they did increase the rates on longer-term deposits. According to Patrick Canion of ipac Western Australia, most mortgage holders are also shareholders of the banks through their super fund, so they stand to benefit from the banks' decision to shore up their balance sheets and protect their investors.

"Most mortgage holders have a super fund, so they are on both sides of the coin," he said.