Why Melbourne Western Suburbs Just Saw Petrol Prices Jump Over 40 Cents as the Price Cycle Strikes Again

*29th December 2025, 2:15pm AEDT*

To understand what just happened to petrol prices in Melbourne's western suburbs, we need to look at one of the most fascinating patterns in Australian fuel economics: the price cycle.

Motor­ists in Sunshine woke up this morning to find unleaded petrol prices had jumped a staggering 40.7 cents overnight, climbing from 162.7 cents to 203.4 cents per litre. This is not random pricing or price gouging. This is the price cycle doing exactly what it always does.

Understanding the Price Cycle

Here is what is happening and why it matters for your wallet.

The petrol price cycle works like a predictable wave. Prices gradually fall over several days or weeks as stations compete for customers, then suddenly spike back up in a matter of hours. Think of it this way: imagine a group of shops all slowly dropping their prices to attract customers, then collectively raising them back up once they have squeezed margins as low as they can go.

The key factor here is market dynamics. When prices hit rock bottom, stations are essentially selling petrol at barely any profit. That position is unsustainable, so the cycle resets.

The Numbers Tell the Story

Looking at today's data across Victoria, we can see the cycle hitting multiple suburbs simultaneously:

You might be wondering why some suburbs see bigger jumps than others. The reason behind this is competition intensity. Areas with more servos competing aggressively tend to fall further during the discount phase, which means they have further to climb when the cycle resets.

What About [E10](/fuel/e10) and Other Fuels?

Craigieburn motorists who fill up with E10 are seeing prices jump 24.2 cents today, moving from 153.8 cents to 178.0 cents per litre. This is because E10 follows the same cycle pattern as standard unleaded, typically sitting about 3 to 5 cents cheaper.

Premium fuels are also affected. In Craigieburn, Premium 95 increased 20.0 cents to 191.9 cents, while Premium 98 climbed 16.1 cents to 196.4 cents.

The Bright Spots

Let me explain where you can still find better value. Not every suburb resets at exactly the same time. While western Melbourne cops the increase, some outer areas remain competitive.

Thomastown in the northern suburbs still has diesel averaging 178.1 cents across 8 stations. Reservoir shows similar pricing at 178.3 cents.

For drivers in the southeast, Cranbourne West maintains diesel at 174.6 cents average, with the cheapest station offering 165.9 cents. Doveton sits at 177.1 cents.

The Economics Behind the Timing

Think of it this way: why does the cycle reset now, during the holiday period?

Travel demand during the summer holidays means more motorists are on the road. Stations know drivers heading away for New Year celebrations need fuel regardless of price. This creates what economists call inelastic demand. Essentially, people will buy petrol whether it costs 165 cents or 205 cents because they need it to reach their destination.

The Victorian state average for diesel sits at 186.5 cents today, but the spread tells the real story. The cheapest station in Victoria offers 159.9 cents while the most expensive charges 345.9 cents. That is a spread of 186 cents between best and worst.

What Should You Do?

Understanding these patterns helps you predict where prices are heading next and plan accordingly.

If you are in western Melbourne today, you have likely missed the low point. However, surrounding suburbs that have not yet reset offer temporary relief. Check Yarraville or Deer Park where competition remains intense.

For those planning New Year road trips, consider filling up in regional towns like Bright where diesel averages 167.9 cents, or Moe at 174.6 cents. Regional Victoria often lags behind metropolitan cycle movements by a day or two.

The pattern typically takes 2 to 3 weeks to complete a full cycle in Melbourne. Prices will gradually fall again over the coming weeks before the next reset.

The Bigger Picture

Comparing states, Victoria's diesel average of 186.5 cents sits below New South Wales at 188.7 cents but above Western Australia at 185.4 cents. South Australia jumped 6.8 cents overnight to 201.1 cents, reflecting similar cycle dynamics.

The lesson here is straightforward: fuel prices are not arbitrary. They follow predictable patterns driven by competition, demand, and market forces. Once you understand the cycle, you can time your fill ups to consistently save 20 to 40 cents per litre.