Price of petrol + Big Mac + Bank interest rate in Australia September 2025

Welcome to my updated monthly report on key financial figures for Australia. I am doing this to keep historical notes through my life. These figures reported are what I see at the various places and an aggregate.

The price of petrol I paid during September 2025 probably averaged $1.90 for unleaded 91 Octane. Add up to 15c for 95 or 25c for 98. It’s relative of course due to fluctuation. 

The price of diesel was around $1.90 the last time time looked and this the price does not fluctuate much compared to unleaded. Adblue was priced at about $2.00 per litre.  

Following the developments during September in the US market regarding tariffs : The car industry in the 1960s US is a perfect example of what happens when you use tariffs to protect an inefficient industry. Has the world forgotten that US cars in that era where expensive, inefficient, unsafe, toxic etc… Regardless Tariffs are still a tax paid y you to your own government. They are not paid by foreigners and it only reduces your buying power rather than anyone else. It’s not the 1960s or 1770s anymore financial markets and manufacturing are much more complicated. 

The price of a Big Mac in September 2025 now averages $8.25. The price for the burger alone does vary from store to store based on location! This time it was the usual shopping centre location. The medium sized meal deal which included fries and a drink costs about $13.45 and the large option was $14.35 as per my monthly visit. As always this is not a fixed price as McDonald’s has a very active app and promotional pricing and freebie schedule.

The RBA – Reverse Bank of Australia the country’s central bank kept the rate at 3.60 % 
The variable home loan interest rate range in September 2025 in Australia was : 4.5% – 9.5%
The saving interest rate range in September 2025 in Australia was : 0 – 4.5%
Note that the rates I saw came with conditions or short term promotion periods – very naughty. 

Note that fuel prices also vary according to area, the level of competition and a whole heap of other factors like shopping discounts, wars, world wide economics and so forth, however unreasonable high prices (relative to crude oil prices) is greed. Also note that the Octane level I post here represents Australian measurement which is different from those in other countries eg. US.

Apart from the actual prices I paid at the servo the websites I use to research the crude oil pricing are:

Australian Institute of Petroleum (Note that they AIP represents the oil companies.)
Index Mundi (Seems independent)