Gas Prices Are Surging Again: Why Fuel Is So Expensive and How to Pay Less
Fuel prices change daily. Compare nearby pump prices, calculate rewards and detour costs, and see when a cheaper station actually saves money.
The short answer
You cannot control crude oil prices, but you can control which station you use, whether a rewards offer actually saves money, and how much fuel you burn. Compare nearby pump prices before driving to fill up; calculate the value of any discount against the station's actual price; and avoid a long detour that eats the saving. There is no reliable “cheapest day” that works everywhere.
In the US, AAA's national figures put regular gasoline at about $4.47 per gallon and diesel at $6.52 per gallon on September 23. A year earlier those averages were about $3.17 and $3.69. That makes regular roughly 41% and diesel roughly 77% more expensive than a year ago. These are national averages, not a quote for your local station. AAA lists September 22's diesel average of about $6.53 as its highest recorded national diesel average.
US regular gasoline: $4.47/gal on September 23, 2026, versus $3.17/gal a year earlier (approximately 41% higher).
US diesel: $6.52/gal on September 23, 2026, versus $3.69/gal a year earlier (approximately 77% higher).
Source: AAA daily national averages. Rounded figures and percentage changes are calculated from AAA's displayed averages. Check again on the day you buy: prices move daily.
AAA reported the regular-gas national average at $4.48 per gallon on September 24, one day after the $4.47 figure above. This is a dated observation, not a live pump price. Read AAA’s September 24 update.
Why are gas and diesel prices rising?
The price at the pump reflects several costs, including crude oil, refining, transport, taxes and the retailer's margin. In a September 10 update, AAA linked the rise in US gasoline prices to climbing crude oil prices and volatility around the Strait of Hormuz. An Australian competition regulator update on September 18 also reported higher retail petrol and diesel prices across its monitored locations, influenced by higher international refined-fuel benchmarks.
Diesel and gasoline need not move in lockstep. Treat a headline about the national average as context; your next fill-up depends on local supply, competition and the price posted at a station today.
Where should you look for the cheapest station?
US: Start with AAA's national and state price pages to see the broader trend, then check nearby individual stations using a fuel-price app. AAA says its mobile app can show nearby stations and often their current prices. Confirm the posted pump price before filling up because app listings can lag.
UK: Use a local station finder rather than comparing the US gallon figure with UK prices per litre. The RAC's Fuel Watch explains that local prices vary and points drivers to its myRAC Fuel Finder to compare stations within two, five or ten miles.
Australia: Use a state-specific fuel-price app or website. The ACCC lists options by state and publishes buying tips for regular unleaded petrol in Sydney, Melbourne, Brisbane, Adelaide and Perth. Those petrol-cycle tips do not apply in the same way to diesel or most regional areas.
The cheapest sign on a map is not always the cheapest trip. For a 12-gallon fill, a 10-cent-per-gallon difference is $1.20. If reaching the cheaper station costs you more than that in extra fuel and time, use a nearer one. In litre-based markets, multiply the price difference per litre by the litres you expect to buy.
Do fuel rewards and loyalty cards save money?
Sometimes. Compare the final price per gallon or litre after the discount with another nearby station's ordinary price. A five-cent discount at an expensive forecourt can still cost more than buying without rewards elsewhere.
Check whether a reward requires minimum grocery spending, expires quickly, has a cap on litres or gallons, or must be activated first. Do not buy extra groceries merely to unlock fuel points. If you use a cashback credit card, count any annual fee and interest; cashback loses its value if you carry a balance. The RAC also advises paying card balances in full when using fuel cashback.
Is Costco fuel worth the membership?
Only calculate this from prices you can actually use. Compare the nearest Costco pump with a convenient alternative of the same fuel grade, then estimate:
Annual fuel saving = price difference per gallon × gallons you would realistically buy there in a year − extra driving cost.
Compare the result with the membership fee if fuel is your only reason for joining. If you already have membership for other purchases, the fee may not be an additional fuel cost. Check opening hours, queues, available fuel grades and whether the station is on a route you already drive. Do not assume a warehouse pump is cheapest on every visit.
When is the best time to fill up?
There is no universal day of the week that guarantees the lowest price. Check current prices around your usual routes and fill up when a convenient station is competitive. Avoid waiting until the tank is nearly empty: urgency takes away your ability to compare.
In Australia's five largest cities, petrol price cycles can create meaningful windows to buy, but their timing differs by city. Use the ACCC's city-specific buying tips and charts, updated several times a week, instead of following a blanket “buy on Tuesday” rule. Diesel generally does not follow those retail petrol cycles.
Cut the amount of fuel you need
Price hunting helps only at the pump. Combining errands, avoiding unnecessary trips and driving smoothly can lower the total you buy. Keep tyres at your vehicle manufacturer's recommended pressure, rather than inflating them to the maximum shown on the tyre sidewall. The US Department of Energy's efficient-driving guidance explains how driving behaviour and maintenance affect fuel use. Use the fuel grade recommended for your vehicle; buying a higher grade without a vehicle requirement may raise your bill without a useful benefit.
Will prices fall soon?
No one can responsibly promise a date. A sustained fall in crude or refined-fuel costs could ease prices, while new supply disruptions could push them higher. Retail prices may react with a delay and vary by area. Check AAA for the US, RAC Fuel Watch for the UK and ACCC fuel monitoring for Australia before a major journey.
What to do before your next fill-up
- Look up the same fuel grade at three stations close to a route you already take.
- Compare the actual pump prices, then apply any rewards or cashback.
- Multiply the price gap by the amount you need; subtract the cost of a detour.
- Check the posted price and reward terms at the pump before paying.
- Keep a note of the cheapest convenient stations and repeat the comparison next time.
The detour test: count fuel and time
A lower pump price is not automatically a cheaper fill. Use this calculation before leaving your normal route:
Net cash saving = gallons bought × price difference − extra miles ÷ your fuel economy × fuel price.
Here is an illustrative US trip, not a station quote. Buying 12 gallons for 15 cents less saves $1.80. An extra six miles in a car returning 30 mpg uses 0.2 gallons. At an assumed $4.36 a gallon, that detour costs $0.872. You keep about $0.93, before accounting for your time.
| Illustrative input | Result |
|---|---|
| Pump saving: 12 × $0.15 | $1.80 |
| Detour fuel: 6 ÷ 30 × $4.36 | $0.87 |
| Cash left after detour | $0.93 |
| Optional value of ten minutes at $15/hour | $2.50 |
If you value those ten minutes at $2.50, the trip costs more than it saves. That time value is your choice, not a compulsory charge. If the cheaper station is already on your route, the extra mileage could be zero and the same offer becomes more attractive.
For a metric example, 50 litres at six cents less saves $3. Driving an extra eight kilometres at 7 L/100 km consumes 0.56 litres; at an assumed $1.50/L that costs $0.84, leaving $2.16. Keep all inputs in the same currency.
Check a local quote immediately before travelling. National averages cannot tell you which nearby station is cheapest. Record the final receipt price, including any rewards conditions, so your next comparison uses the discount you actually received.
*Worked examples added 9 October 2026. Hypothetical inputs are labelled and are not live offers or forecasts.*
Common questions
Does a fuel app always show the exact pump price?
No. Prices can change between an app update and your arrival. Treat the app as a shortlist and verify the station's displayed price.
Should I drive across town for cheaper gas?
Do the maths first. A small discount on one tank can disappear after extra miles and time. A station on your existing route is often the better choice.
Is premium gasoline a way to get better value?
Follow your vehicle manufacturer's fuel requirement or recommendation. Paying for a grade you do not need is not a reliable way to cut your fuel bill.
Will a membership or loyalty programme always pay for itself?
No. Use your actual fuel volume, pump prices, membership cost and extra travel to calculate its value. Compare the discounted final price with nearby alternatives.