NAB is sacking over 6,000 employees in an automation drive it says will save up to $1 billion.

The deep cuts were announced this week alongside news of a 2.5 per cent growth in profits to $6.6 billion.

Thousands will go over the next three years, expenses will be slashed and money poured into new technology, NAB chief Andrew Thorburn announced this week.

NAB currently employs just under 33,500 full-time equivalent staff.

The bank says it plans to maintain its dividend for the next year while also investing an extra $1.5 billion over three years.

The automation drive will involve the hiring of around 2000 people with technology skills to reduce costs for the future.

“We're going to be disciplined on costs, and targeted on costs, and serious about costs. But I think it's about efficiency more than costs,” Mr Thorburn told reporters.

“We need to be ready for a world where our competitors and maybe the growth outlook will be such that costs and efficiency will be at premium.”

Analysts see the move as the latest in growing trend toward deep-seated change in financial services, where digital transformation are shifting banks' internal workings.

Competition from new rivals is forcing change too, with fintech start-ups beginning to take a share of business from banks.

Finance Sector Union national secretary Julia Angrisano  said NAB is putting “technology and profits before people”, and that the bank should retrain staff rather than make them redundant.

“NAB, along with the rest of the banking industry, has a long-term social responsibility to their workers. This is especially so in a period of intense digital disruption,” she said.

Mr Thorburn said some existing staff would be moved into new jobs where possible, while other cuts would come through natural attrition.

The bank says it is establishing a transition program to help employees find new jobs outside NAB, he said.