Globally and locally, there is growing interest in restoring shellfish reefs and the ecosystem services they support. Successful restoration requires that present-day environmental conditions are suitable for the growth, survival and reproduction of oysters and their provision of desired ecosystem services. Stakeholder and community support is a key factor for ensuring successful restoration outcomes, as any potential conflicting use of the restoration area needs to be addressed and minimised. In Australia, the Reef Builder project is aiming to restore shellfish reefs at 13 locations across Australia. Over the past two years, a restoration suitability modelling process has been applied across all sites including: 5 States, 12 estuaries and 4 shellfish species, to inform site selection for shellfish reef restoration. Here we present the stakeholder-supported restoration suitability modelling process and results for Sydney Harbour, considering: (1) how environmental conditions within Sydney estuaries match biological requirements of two native (Sydney rock: Saccostrea glomerata; flat: Ostrea angasi) reef-forming oysters, (2) conflicting estuarine uses, and (3) amount of public support for oyster reef restoration in Sydney’s estuaries. Additionally, we compare this case study to other shellfish restoration suitability modelling projects conducted in the country, and discuss lessons learnt.