NAB has extended its offer to pay the $700 mortgage early exit fee charged by CBA and Westpac for customers who choose to switch to NAB.

The move, which is part of NAB's aggressive campaign to 'break up' with the big four and steal a share of their custom, is available to existing CBA and Westpac mortgage holders who switch to NAB's lower standard variable home loan rate.

The number of CBA and Westpac customers that have made the switch to NAB has increased by 43% and 37% respectively since the campaign was launched, said NAB personal banking group executive Lisa Gray.

"NAB remains committed to ensuring that all Australians are able to walk downthe street and get a better deal - despite some banks, with higher home loansrates, choosing to restrict their customers from accessing these better rates bycharging early exit fees," she said.

With new legislation banning exit fees set to come into effect from July, NAB has just two more months to make further inroads into CBA and Westpac's share of the mortgage market before its exit fee offer becomes redundant.

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