Melbourne's cycle looks like Sydney's, but the data is slower
Melbourne runs a 14-28 day discount cycle similar to Sydney's — a sharp 10-30¢/L jump followed by a slow grind down over the next three to four weeks. What's different is the data: Victoria's Fair Fuel scheme publishes a daily price cap (the maximum a station has committed to charge that day), not real-time changes. Stations are allowed to sell below their cap without updating the feed, so the listed price is a ceiling, not always the truth at the bowser. PetrolPulse's metro average is the best available signal for timing, but expect occasional surprises at the pump.
Geelong has a refinery — it doesn't make Melbourne cheaper
Viva Energy's Geelong refinery is one of only two operating refineries left in Australia, supplying a meaningful share of Victoria's petrol. Despite that, Melbourne pump prices track Singapore wholesale parity (the MOGAS benchmark) just like every other capital. The refinery doesn't translate to a local discount because Viva sells into the same wholesale market as importers. The cycle and the macro signals are what move your price, not where the fuel was refined.
Western and northern corridors are reliably cheaper
The most aggressive discounters — 7-Eleven, Liberty, United, Costco — cluster heaviest in western (Sunshine, Werribee, Footscray) and northern (Broadmeadows, Craigieburn, Epping) Melbourne. Inner south-eastern suburbs and the bayside corridor consistently run 5-12¢/L above the metro median because branded major stations dominate and there's less competitive pressure to drop first. If you commute through the west or north on a normal day, fill up at the far end of the trip rather than near home.