C1 costs for the December quarter were a record low US$12.08 per wet metric tonne, down by 4% and closer to the full-year guidance range of $11-12/wmt.
Shipments were 40.5 million tonnes of iron ore, down by 4% quarter-on-quarter.
FMG CEO Nev Power, who will step down next month, said the team delivered another strong quarter.
“Our productivity and efficiency initiatives have continued to reduce the cost base offsetting higher strip ratios, exchange rates and fuel prices,” he said.
“Our focus on improving safety continues, together with our clear market and product strategy to deliver value to our customers, generating strong cash margins and shareholder returns."