The milestone was achieved on the morning and evening tides, with 2.02Mt exported through the period.
The morning tide saw 1.02Mt exported on five vessels, with the first outbound ship at 6.40am.
The evening saw a further 1Mt sail out on six vessels, with the last leaving at 10.15pm.
It was the first time the port had breached the 2Mt level, with the PHPA managing 24 vessel movements in the 24-hour period.
This month also saw a new record achieved for the largest amount of product exported on a single tide, with 1.1Mt recorded on April 6.
The new milestone is the latest growth story for Port Hedland, which marked record throughput in December despite Tropical Cyclone Christine forcing a temporary closure.
The port recorded a 12% year-on-year increase in December to 30Mt, beating the previous September record by 300,000t.
BHP Billiton, Fortescue Metals Group, Atlas Iron and BC Iron are among the iron ore producers that export through Port Hedland.