TL;DR: With Brisbane metro ULP at a record 239.7 c/L today, the tax in a litre is 74.4 c — 52.6 c of flat federal excise plus 21.8 c of GST — which is 31.0 percent of the pump price, not 40. The “40 percent is tax” line only ever held near the cheap end of the cycle: at July’s 167.9 trough tax was 67.9 c, or 40.4 percent. As the price rose to today’s record, the share FELL, because excise is a flat charge and only the GST slice grows — and it grows slower than the price. The 30-odd cents that took you from August’s ~209.9 peak to today’s 239.7 was NOT the government: the tax in a litre moved under 3 c (71.7 to 74.4). Blaming tax for a price spike is backwards — a spike dilutes the tax share.
Petrol just hit a record. Brisbane metro ULP median is 239.7 c/L today, and the mood at the servo counter is exactly what you’d expect. “Nearly half of that is tax.” “The government’s gouging us.” It’s the loudest I’ve heard the 40-percent line in months, and the price spike is why. So let me do what I always do: ask for the number, and show the working.
The claim
The folk figure is durable: “40% of what you pay for petrol is tax.” It gets louder every time the price jumps, because a jump feels like the moment to be angry at the government. Two things are being claimed at once — that the tax share is around 40 percent, and that a spike like this one is the government’s doing. Both are checkable, and both turn out to be wrong at today’s prices.
What we checked
Two of the three numbers here are not ours to move, and I want to be straight about which is which.
The federal fuel excise is a flat per-litre charge — an ATO rate, the same whether petrol is dear or cheap. Since 1 August the excise relief is over and the full indexed rate is back in force at 52.6 c/L (my colleague Tom walked through that cliff in what your next full tank costs). GST is one eleventh of the pump price you actually pay. Both are government rules — ATO and the excise schedule — that we’re quoting, not data we derived.
The third number, the pump price, is the one we serve: the live QLD Government feed. So we took today’s Brisbane metro ULP median — 239.7 c/L, a record — and did Karen’s sum from how much of a litre of petrol is actually tax: (excise + price ÷ 11) ÷ price.
What the data shows
At 239.7 c/L, excise is the flat 52.6 c and GST is 239.7 ÷ 11 = 21.8 c. Together that’s 74.4 c of tax, or 31.0 percent of the pump price. Well under the folk 40 — and, it turns out, the lowest point of the cycle.
That last part is the counterintuitive bit, so here it is slowly. Excise is flat, so as the pump price climbs, only the GST slice grows, and it grows slower than the price. The tax percentage therefore falls as the price rises. Karen showed this before the record; today’s price just pushes it to the extreme.
Walk it across the cycle at today’s full 52.6 c excise:
- At July’s trough, 167.9 c/L, tax was 67.9 c — 40.4 percent. That is where the folk “40 percent” lives: the cheap end.
- At August’s cycle peak, 209.9 c/L, tax was 71.7 c — 34.2 percent.
- At today’s record, 239.7 c/L, tax is 74.4 c — 31.0 percent.
So the “40 percent” figure describes the cheap end of the cycle. Today is the opposite of the cheap end — it’s the record — which is exactly why the share is at its lowest.
The spike wasn’t the government
Here’s the kicker that the “gouging” line gets exactly backwards. The 30-odd cents that pushed you from August’s ~209.9 peak to today’s 239.7 record was not tax.
Do the two tax bills side by side. At 209.9 the tax in a litre was 71.7 c. At 239.7 it’s 74.4 c. That’s a rise of under 3 cents — while the pump price rose about 30. The excise didn’t move at all (it’s flat), and the GST only crept up 2.7 c because it’s one eleventh of a price that rose 30. So of the ~30 c spike, the government took under a tenth. The other 27-odd cents was the barrel and the retailer.
That’s why blaming tax for a price spike is backwards: a spike dilutes the tax share. The angrier the record makes you feel about the government’s cut, the smaller that cut has actually become as a fraction of your bill.
The verdict
“40 percent of what you pay is tax” is false at today’s prices. It’s about 31 percent — the lowest point of the cycle. The folk figure isn’t invented; it describes the cheap end of the cycle, near the trough, where the flat excise is a big slice of a small number. Today we’re at the record — the dear end — so the share is at its floor. Repeating “40 percent” during a price spike is describing the opposite of where we are.
So what, for you
Two plain things follow. First, the tax on a litre barely moves week to week — excise is fixed and GST shifts by cents. When the pump price jumps 30 c, that is not the government; that is the barrel and the cycle. Second — and this is Karen’s point, worth crediting again — a lower tax share is not “cheaper.” Today you’re paying a bigger bill of which a smaller fraction is tax. The flat excise is a smaller slice of a bigger number; that’s arithmetic, not a discount. Nobody’s giving you anything at 239.7.
The lever you can actually pull is timing and where you fill, not the tax. At a record, the spread between servos is where the only saving lives — today’s prices around you are on the Pinly Fuel map, off the same QLD Government feed these numbers come from.
How we measure: only the pump price is ours — Brisbane metro ULP median from the live QLD Government feed, one metro, one grade, one day (23 Sep 2026). The 52.6 c/L full indexed excise and the one-eleventh GST are ATO and government rules we’re quoting, not our data; the relief ended 1 August, so the full rate is in force. The trough (167.9), August peak (209.9) and record (239.7) are daily medians across the cycle, not the single cheapest or dearest station ever. And “lower share” is not “cheaper” — it’s a bigger bill where a smaller fraction is tax, because a flat excise is a smaller slice of a bigger number. Your own suburb on your own day will differ by a few cents, but the shape holds: the tax share is highest when fuel is cheapest, and lowest — about 31 percent — at a record like today’s.
— Priya