NAB, like CommBank, is keeping 0.05 per cent. This mean it will pocket an extra $108 on annual repayments for customers on a $300,000 variable-rate loan and more than $180 from a $500,000 mortgage.

Westpac last night withheld 0.03 per cent, taking $66 on a $300,000 loan and $109 from a $500,000 figure.

‘CREAMING' EXTRA INTEREST

CommBank is currently lending nearly $288 billion at variable rates, according to its financials and Australian Prudential Regulation Authority data, meaning that by playing scrooge, it can cream off $144 million in extra interest.

NAB is estimated to be extending about $180 billion, so it reaps an additional $90 million. Westpac lends $263 billion, leading to a windfall of $79 million.

“These banks are hardly on struggle street, and their mortgage customers deserve better,” said Matt Levey, director of campaigns at consumer watchdog Choice.

PROFIT EXPLOSION

CommBank's latest financial results, published yesterday, reveal it is making $1 million of profit every hour of every day. Its net profit for the first three months of 2015 was $2.2 billion.

NAB's most recent result, published in February, showed it was making $820,000 an hour after tax. Its net profit for the final three months of 2014 was $1.8 billion. NAB will post new profit figures today.

Westpac is making $835,000 an hour and about $1.8 billion a quarter.

It was commonplace for the majors to hold back a portion of cash rate reductions by the Reserve Bank of Australia between 2011 and 2013, supposedly due to “funding cost pressures”.

But that is not the excuse this time.

In fact, ANZ yesterday told News Corp Australia there is no new “cost pressure”. On Tuesday it swiftly passed on the RBA cut in full.

“ANZ makes it decisions each month after an assessment of funding costs and decided to pass the whole amount on,” said spokesman Paul Edwards.

‘CAREFULLY CONSIDERED NEEDS'

CommBank argues it is ploughing some of the skimmed proceeds into helping savers.

Yesterday it said more than one million customers will likely benefit from its decision to hike interest rates on an eight-month term deposit popular with retirees and an account favoured by younger customers. As things stand, its other six million deposit customers will get no benefit.

Westpac increased its nine-month deposit rate to match CBA.

NAB has not increased rates on any savings products.

In a statement, Group Executive for Personal Banking Gavin Slater said it had “carefully considered the needs of customers and shareholders and the current economic and regulatory environment” before deciding to only cut its standard variable rate by 0.2 per cent.

NAB did not return calls prior to publication.

NAB and Westpac, in their statements, highlighted the fact they had transmitting the cut in full to business customers.

‘FIGHT' FOR YOUR FULL CUT

Savvy mortgagors could wrest the rest of the rate cut from the banks — and then some, said RateCity research manager Peter Arnold.

Armed with information about competitor offers, home-loan customers were commonly negotiating rate drops of up to 0.15 per cent.

“Fight for that discount and be ready to walk if they won't give you what you consider a good deal,” Mr Arnold said.