The Australian bank announced the sale this morning via its announcement to the ASX, along with the banks full-year profit of $6.34 billion (up 19.7 per cent on last year).

The sale will see the Japanese insurer purchase the life insurance business for $2.4 billion, while NAB will retain 20 per cent of the business.

NAB will retain ownership of its existing investments business which includes the superannuation, platforms, advice and wealth management. According to NAB, the economic risks and benefits of 80 per cent ownership will pass to Nippon Life from 28 October 2015.

NAB will retain responsibility for the management of the life insurance business until the completion of the sale.

The transaction is expected to be completed by the second half of calendar 2016 subject to regulatory approvals, establishment of the life insurance business as a standalone entity and extraction of the superannuation business from MLC.