The two bodies will exchange data based on the international Common Reporting Standard (CRS) which has been endorsed by the OECD and the Global Forum for Transparency and Exchange of Information for Tax Purposes, they said in a joint statement.
Automatic exchange of financial account information (AEOI) will begin by September 2018. Each country will send details of accounts held in its jurisdiction by the other country's tax residents.
"Both jurisdictions are satisfied with the confidentiality rules and data safeguards that are in place in the other jurisdiction to ensure the confidentiality of information exchanged and prevent its unauthorised use," the IRAS and ATO said.
"Singapore and Australia have taken another step in enhancing cooperation to support greater tax transparency and fight against tax evasion. Both jurisdictions will work toward implementing AEOI with other major financial centres to ensure a level playing field," they said.
Singapore made changes to its tax laws in May to allow it to implement CRS.