What Gas Costs and Why · Published · Updated
A price on a filling-station sign compresses a long supply chain into one number. The purpose of a breakdown is to make that number easier to question. How much reflects oil? How much pays for processing and delivery? How much goes to government? Those questions are useful, but the answers depend on the source and the date. A convincing-looking chart is not enough. You need to know what its components actually measure.
Start with the methodology and the source named under the chart. Our pages distinguish a published breakdown from a derived one. A published breakdown reproduces categories supplied by an official source. A derived breakdown calculates part of the price from other observations and leaves a combined residual. Both can be informative. They answer slightly different questions, and neither is a receipt from the particular station where you filled up.
Read the total before the components
Check the product, currency, volume unit and date before comparing anything else. A US gallon is not a litre, and a US gallon is not an imperial gallon. A price in Canadian dollars cannot be compared directly with the same numerical price in US dollars. Regular gasoline and diesel are separate products. European Euro-super 95 also differs from the regular gasoline specification used in US reporting.
For a worked example, imagine a pump price of 1.80 units of local currency per litre. Suppose crude accounts for 0.55, refining and distribution for 0.45, and taxes for 0.80. These are illustrative amounts, not a current market quote. Adding them reproduces the total. The tax share is 0.80 divided by 1.80, or about 44.4%. That is a share of the retail price, not necessarily the tax rate set in law.
A 20% VAT rate does not mean that 20% of a tax-inclusive price is VAT. If the price before VAT is 1.00, adding 20% produces 1.20. The included tax is 0.20 out of 1.20, or one-sixth. Confusing the rate with the share overstates the amount collected. Fixed excise and other duties may be present as well, so the total tax share can be much higher than the VAT share.
What the crude component means
Crude oil is the raw material used to make a range of petroleum products. A simple derived estimate takes a benchmark price per barrel, divides it by the litres in a barrel, and converts the result into local currency. It is an allocation of a common input cost. It does not claim that a refinery buys every barrel at that benchmark or that every litre of crude becomes a litre of gasoline.
The estimate is sensitive to its reference. WTI and Brent can differ. A refinery may buy a mixture of grades, pay freight, hold inventory or operate under contracts. A benchmark gives readers a consistent yardstick, not a complete account of a plant's purchases. This is why our methodology states the yield assumption and regional benchmark rather than presenting the crude bar as an exact physical tracing of your fuel.
What the downstream component means
The combined refining and distribution portion is the amount left after estimated crude and taxes are removed. It can include processing costs, energy, wages, maintenance, transport, storage, retail operations, financing and margins. If oil rises faster than retail prices adjust, the residual can shrink. If product supply is tight, it can grow. Both movements can happen without a matching change in the profitability of any one company.
The EIA's component methodology is useful background for the published US categories. The key reading habit is to resist replacing the word margin with profit. A gross margin covers costs that have not yet been deducted. A national average margin also does not reveal how the result is divided among an independent retailer, a distributor and a refinery.
Where only a pretax price is available, a separate refining bar and marketing bar would imply information the source did not provide. We therefore keep them combined. More colours would not make the result more accurate. A published split can be shown when there is a source for it, but its period and method remain attached to it.
Read the date on every panel
A weekly pump observation and a monthly component estimate often arrive on different schedules. Imagine that the newest pump price is from September while the newest official breakdown describes June. Applying June's percentage shares to September's total would create a new estimate. It would not reproduce either original dataset. The result could hide a substantial change in refining or crude costs between those months.
Our region pages keep these periods separate. The latest price gets its own date. A published monthly breakdown gets its own price and date. To ask what changed over a week, compare weekly observations for the same product and region. To ask how a monthly component changed, compare the monthly series. A delay in publication is worth noticing, but it is not a reason to silently move a number into a later period.
Look for the limits as well as the result
A negative residual deserves attention. It may arise from unusual market conditions, timing differences or an imperfect benchmark allocation. Hiding it would make the chart look tidier while concealing the very issue a reader needs to investigate. We flag negative components and retain signed values. Similarly, a large weekly jump is a reason to check the source, units and dates before giving it an economic explanation.
Missing data is different from zero. A missing tax rate does not make a region tax-free. An unavailable exchange rate does not justify using today's rate for a historical observation. A blank breakdown can be the most accurate presentation when the inputs are incomplete. The reported pump price can still be useful, provided the site does not imply that the unmeasured parts are known.
A practical reading sequence
Use this sequence when opening a region page: identify the fuel and date, read the total, check whether the method is published or derived, inspect the tax definition, and then examine the history. If you are comparing across a border, switch to a common currency and litre basis. If you are comparing nearby locations, make sure their local levies and product grades are comparable.
Finally, separate description from explanation. A chart can show that the downstream portion increased. Establishing why it increased may require refinery information, inventories, shipping conditions or other evidence. The breakdown is a map of questions to investigate. Used that way, it makes the pump price less mysterious without pretending that one chart explains every decision in a complicated market.