Timeline to determine the Default Market Offer applying for 2026–27

On 5 November 2025 we published the issues paper for the 2026–27 DMO determination (DMO 8).

The issues paper seeks stakeholder feedback on how to best adapt our approach to suit the changes to the DMO framework and meet the new policy objective. The AER is also considering some changes in its approach to setting DMO 8 tariffs and prices to ensure it responds to market developments.

Stakeholder engagement is a valuable input to our determination process. The AER will also engage with stakeholders through workshops and bilateral meetings during the consultation period.

On 5 November 2025 we also published Assessing the performance of the wholesale cost model, a supplementary report to the DMO 8 issues paper. This report was developed in response to stakeholder submissions received during our DMO 7 process that called for the performance of the wholesale cost model to be transparently reviewed against actual outcomes that have occurred in the market.

This report is relevant to the percentile estimate discussion in the DMO 8 issues paper. However, it is an independent report which stakeholders do not have to read in order to engage with the issues paper consultation process.

We invited stakeholders to make written submissions on the DMO 8 issues paper. Submissions closed on 26 November 2025. Public submissions received are published below.