Westpac New Zealand's cash earnings shot up by 56 per cent to $1.01 billion in the year to September, boosted by a $404 million turnaround in asset impairment charges. 

Net interest income benefitted from a 3 basis point increase in margins and lending growth of 5 per cent driven by $5.7b in mortgage growth. 

Deposits increased by 7 per cent, or $4.9b, which fully funded the bank's loan growth and lifted its deposit-to-loan ratio to 82 per cent, the bank said. 

Westpac said strong momentum in the economy has contributed to a "solid" full year result. 

Acting chief executive Simon Power said Covid-19 was causing significant strain and uncertainty for parts of the community but economic activity in the year leading up to the latest outbreak had been very strong. 

Simplicity Founder Sam Stubbs joined Simon Barnett and James Daniels Afternoons and said 'something's wrong here'. 

He says most people don't know what they are paying their banks in fees and so banks are thriving on this ignorance. 

"If you're making that much money and your customers are that unsatisfied, and it's so hard to compete, it's probably worth an inquiry."

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