It shipped 40.4m tonnes of iron ore in the first quarter, up 28% from 2013.
Output rose 20% to 35.5m tonnes in the same period.
The group is raising its shipping target for 2015 to 165m tonnes, up from between 155m and 160m tonnes previously.
Australia's third-biggest iron ore miner said it had a cash cost of $25.9 per tonne during the quarter, down 26% year-on-year.
