The International Energy Agency (IEA) and the Institute of Energy Economic, Japan (IEEJ) have developed and published long-term decarbonisation pathways for Southeast Asia and Indonesia. This paper provides a comparison of modelling approaches, quantitative drivers, and results from the IEA and IEEJ pathways, highlighting areas of agreement, as well as identifying and explaining differences, and thereby to derive implications. The IEA pathway used in the comparison is the Announced Pledges Scenario (APS) from the World Energy Outlook 2022 and the Energy Sector Roadmap to Net Zero Emissions in Indonesia. The IEEJ pathway is the net zero CO2 emissions in 2050 or 2060 case (CN2050/2060) from the Decarbonisation of ASEAN Energy Systems: Optimum Technology Selection Model Analysis up to 2060 study.