BHP will make immediate payments of outstanding invoices. The accelerated payment program is expected to deliver about A$100 million more quickly into the hands of the company's small business partners.
BHP will reduce payment terms to seven days from 30 days for more than 1,100 small Australian businesses from next week.
BHP CEO Mike Henry said the company was taking action to reduce the risk of transmission at its sites, offices and in the community.
"Our local and small business partners play a critical role in supporting our operations and our people, and we know this is a very difficult time for them. We must look out for each other as we manage through this together," he said.
BHP has also created a $6 million fund to support its labour hire companies and their employees.
The fund will be used for one-off payments for people quarantined after entering Australia and pay for labour hire employees not entitled to sick leave but affected by COVID-19.
BHP spends about $1.5 billion annually with local Australian suppliers.
The company defines a small business as one generating less than $10 million revenue, regardless of the number of full-time employees.