Synlait Milk (NZE:SML, ASX:SM1) expects fiscal first-half underlying net loss of NZ$33 million to NZ$38 million, compared with an underlying after-tax net profit of NZ$8.7 million a year earlier, according to a Wednesday Australian and New Zealand bourse filing.

The company said it continues to face cost and operational impacts despite manufacturing issues at Dunsandel being largely resolved.

Synlaid said that it required major production adjustments this season to rebuild inventory, leading to additional raw milk sales in the period that pressured margins and increased operating costs.

"We are very disappointed with the six-month result and the impact it has had on the pace of our financial turnaround. However, we have made progress with real momentum in our operations, a renewed Canterbury-based ELT, and the North Island sale set to fundamentally strengthen Synlait," said Chief Executive Richard Wyeth.

Wyeth added that it will at least take 12 months for Synlait to "return to success."

The company's Kiwi shares plunged past 17%, and Australian shares fell past 13% in recent Wednesday trade, reaching their lowest since January 2025 on both stock exchanges.