The telco announced today that it was the founding communications partner for the Sydney-based statup hub.
Stone and Chalk officially opened earlier this year.
"We are delighted to partner with Stone & Chalk to encourage innovation and entrepreneurship in the Australian fintech sector and support local start-ups," Optus Business managing director John Paitaridis said in a statement.
"We are excited to welcome Optus Business as our founding communications partner," Stone & Chalk's CEO, Alex Scandurra, said.
"Working with some of Australia’s largest financial services and technology companies means Optus understands our market, the broader financial ecosystem and its demand for constant innovation.
"We are looking forward to working with the team on our technology and services requirements and supporting our promising start-ups, by either supplying best in breed ICT services, or through access to key Optus specialists, technology leaders, partners and mentors."