Fonterra said it would change its auditor to KMPG from PriceWaterhouseCoopers.
The co-op said that following a formal request for proposal process for external audit services, Fonterra had recommended KPMG be appointed as its new auditor for the financial year to July 31, 2020.
KPMG's appointment is subject to approval by shareholders at the co-op's next annual meeting due in November 2019.
Fonterra's current audit agreement with PricewaterhouseCoopers concludes at the completion of the 2019 year financial statements.
The co-op announced earlier that it had cut its farmgate milk price forecast for 2018/19 to $6.00 to 6.30 kg of milk solids from a previous range of $6.25 to $6.50/kg.