Quarterly data available
Quarterly CPI data can be found in tables 17 and 18. From December 2025, the quarterly CPI data is calculated as the average of the three relevant monthly indexes. Data for the most recent quarter will be added to tables 17 and 18 when the monthly CPI is published for the months of March, June, September and December.
Re-referencing the quarterly CPI data
The previously published quarterly data has been re-referenced and aligned to the new monthly CPI series. September 2025 serves as the link period where the index equals 100.00. While the level of the quarterly indexes has changed due to re-referencing, the percentage movements of the index have not been revised.
Conversion factors and examples of how to use them are available in the Quarterly CPI - September 2025 Conversion Factors spreadsheet in the Data downloads. These factors enable users to convert the re-referenced indexes to the previous reference period of 2011-12 = 100.0.
More information on re-referencing is available in Re-referencing the quarterly Consumer Price Index.
Quarterly Trimmed mean
As announced in July 2025, the ABS will continue to produce the quarterly Trimmed mean based on pre-October 2025 methods. The quarterly Trimmed mean data is available in Appendix 1. More information on the quarterly Trimmed mean is available in Quarterly Trimmed mean explanatory note.
Postponing the annual CPI weight update
Since 2018, the ABS has updated the CPI weights annually. The updated weights are usually implemented in the CPI for the month of January and March quarters. With the introduction of the complete Monthly CPI in late 2025, the ABS has decided to postpone the next CPI weight update to January 2027. The ABS will monitor household spending patterns throughout 2026 and consider a mid-year weight update if needed. The ABS will advise users in advance if a mid-year weight update is going to occur. Information on the 2025 weight update is available in Annual weight update of the CPI.