The appointment has been announced after Mr Kozarcanin advised the company he would be stepping down after leading the business through its formative start-up and scale-up years.
Mr Heintz brings extensive executive experience, most recently serving as CEO of Hazeldenes, one of Australia's leading poultry producers.
He has also held senior leadership roles within the dairy industry.
Honestly Riverina Ltd believes its consumer brand, Nice Rice, is well positioned in major supermarket chains to continue a strong growth trajectory.
It says it is exporting Australian rice to Japan and New Zealand, becoming the first business to capitalise on the opening of these important export markets.
Revenue has increased 156 per cent year-on-year, supported by continued capital investment, expanding manufacturing capability and the creation of local employment opportunities throughout Jerilderie and the wider Riverina.
Board chair Steven Chaur thanked Mr Kozarcanin “for his tireless commitment, vision and leadership in establishing Honestly Riverina as one of Australia's fastest-growing rice businesses”.
"Mirza has played an instrumental role in taking Honestly Riverina from an ambitious idea to a thriving business with strong foundations," Mr Chaur said.
"His leadership has helped build a business that is now growing across retail, industrial and export markets, while creating new opportunities for Australian rice growers and regional communities.
“We are incredibly grateful for his dedication and wish him every success as he pursues opportunities across his other business interests in the technology and mining sectors."
Mr Kozarcanin’s final public engagement as CEO will be at RiceConnect in Barham this week, where he will speak alongside a delegation of Honestly Riverina board members and senior management before formally handing over the role at the end of the month.
"We are delighted to welcome Mark (Heintz) to Honestly Riverina,“ Mr Chaur said.
“His proven leadership, commercial expertise and passion for Australian agriculture align perfectly with our vision as we continue to expand our retail, industrial and export businesses, invest in regional Australia and create lasting value for our growers, customers and communities.”