Fonterra sold 316,000 tonnes of dairy ingredients in May this year, 30,000 more than its previous record for one month. The dairy co-op added that sales to the US during its 2005/06 season had also topped the US$1bn (€784m) barrier for the first time.
The news shows how Fonterra has continued to grow on the world dairy market, providing stiff competition for European firms.
"The sales figures reflect both a huge effort by the ingredients manufacturing and sales teams and the benefits of a three year effort to improve efficiencies in Fonterra's cow to customer supply chain," said John Shaskey, managing director of Fonterra Ingredients.
He added that sales had continued strongly into June and July, although warned the group's cashflow could be hit in the short-term as it waited for customer payments.
Fonterra, already the world's largest dairy product exporter, said its more efficient business model made it well-placed for future growth.
The co-op processed a record 14bn litres of milk in the full year up to 31 May, and was recently named the fifth largest dairy firm in the world by Leatherhead International.
Leatherhead said Fonterra's $8.69bn annual sales put it ahead of Several European big hitters, including Arla Foods, Friesland Foods and Lactalis.
World prices for dairy products are expected to remain relatively stable though somewhat lower than in 2005, according to a forecast by the UN's Food and Agriculture Organisation (FAO).
The prices reflect increasing supplies on the market, meeting the increasing demand for dairy products. On internal EU markets, commodity prices fell at the start of July as part of the European Commission's Common Agricultural Policy reform.