After about half of the 450 workers at BHP's bulk export terminal in Western Australia's Port Hedland downed tools earlier in July over pay and conditions, members of the combined Ports Unions have announced they will strike again from August 8.
The first strike was the first major industrial action to hit the resource-rich Pilbara region in decades, with estimates it could have cost BHP $50 million in lost revenue and the state $6.8 million in royalties.
Ports Unions claims the mining giant has failed to bargain in good faith since then, leaving workers with no choice but to take further action.
"This action is the direct result of the company's failure to negotiate seriously," Australian Manufacturing Workers Union WA state secretary Steve McCartney said.
"This action is the direct result of the company's failure to negotiate seriously."
A 24-hour ban on loading ships will be imposed on August 8, followed by a 24-hour work stoppage from 5.30am the following day.
High voltage and power workers, who are negotiating a separate agreement with BHP, will down tools for 12 hours on August 9.
The new stop-work moves follow a meeting of workers on Thursday night to consider further protected industrial action.
"We have given ample opportunity for BHP to come to the table with a fair offer that addresses our members' concerns," Western Mine Workers Alliance spokesperson Craig Beveridge said on Friday.
"Instead of engaging in the bargaining process, BHP continue to delay, distract and waste time."
Bargaining for BHP's port operations agreement started in October 2025.
The unions previously said BHP has failed to progress wage-bargaining talks for more than six months.
About 577 million metric tonnes were exported from Port Hedland in 2024/25, worth an estimated $115.8 billion.
The company said it paid $2.8 billion in state royalties and related government payments in the 2025 financial year, contributing about nine per cent of all WA government revenue.
The Electrical Trades Union, the Western Mine Workers' Alliance (Australian Workers Union), and the Australian Manufacturing Workers' Union are involved in the industrial action.
AAP has contacted BHP for comment.