Cheap petrol & diesel
While fuel prices have dropped slightly in recent weeks, petrol and diesel are still both up by 28p/L on January 2021, and with the RAC saying drivers have been paying millions more than they should for petrol, it's crucial to save on filling up by buying in the right place. And, if you take steps to drive more efficiently, it's possible to cut costs further...
Step 1: Make your car more fuel-efficient
Some simple checks and adjustments to your vehicle can help reduce fuel consumption (thanks to the RAC for its input in compiling this list). Combined with the tips below on driving more efficiently, these could help save up to 30% on fuel costs – and of course, they're a quick and painless way to benefit the environment too.
Lower tyre pressures increase drag on a car, meaning you need more fuel. So regularly check the pressures are correct (overinflating your tyres will also use more fuel) and your car will need less oomph to keep it moving.
The lighter your car is, the less effort it needs to accelerate. By clearing out junk from the boot and not carrying any unnecessary weight, you can save a little more money. Any extra weight you ride around with ups your fuel consumption – while lightening the load won't make the biggest difference, every little helps towards keeping it down.
A roof rack, even unused, adds wind resistance to a car, increasing drag and making the engine work harder. If you don't need it, take it off, along with anything else inefficient. Even closing the windows and removing any flags will make the car run slightly more efficiently.
Air-conditioning uses engine power and therefore fuel – so make sure it's turned off unless you really need it. The general consensus is it's more efficient to drive with the windows down and the air-con off at lower speeds, but at higher speeds it's better to use the air-con and keep windows up due to the extra drag caused by having windows down.
If you're not using your air-con, it's worth turning it on once in a while as not using it can mean it stops working.
Fuel is heavy, so by filling the car up you're adding quite a weight. The less fuel your car has in it, the more efficiently it drives. If you fill up slightly more often and put less in (to 1/2 or 3/4 full), it'll make the car run more efficiently.
On long, flat roads, cruise control helps you save on fuel by maintaining a constant speed, thus removing unnecessary acceleration. But used regularly on roads that aren't flat, it will increase how much fuel you use because it's slower to react to changes in gradient, meaning it will accelerate for longer than a driver would when going up a hill. Motorways are usually flat, so reserve it for when you can cruise along.
Step 2: Seven tips to drive more efficiently
You can drive the same distance in the same car, without slowing down, but using less fuel – better for your wallet, better for the environment. The key is to drive smoothly. Here are the seven tips you need to know.
Speed up smoothly. The harder you press on the accelerator, the more fuel will flow – but you can reach the same speed using much less power. As a rough rule, stay under 3,000 revs. Plus, if you accelerate too quickly, chances are you'll then have to brake hard, which isn't exactly efficient.
Always drive in the highest gear possible without labouring the engine. So change up much earlier than feels natural – it'll take some pace out of your acceleration, but as that's our first tip it isn't a bad thing. If you have a fuel efficiency display, you'll be surprised how immediate an impact this has.
All the other tips require you to be alert and aware of your road position. This helps you plan ahead and move gradually. It also means that more efficient driving is also safer driving.
Where safe, allow yourself to slow naturally rather than hitting the brakes. When you press the brake you are effectively converting the energy you've paid to put into the car into heat. Instead, where you can, make the most of the car's momentum – good road positioning is crucial for this. Over the course of a journey if you brake frequently, you'll end up having to accelerate more too, which ultimately means using more fuel.
If you hear sharp acceleration and screeching brakes you know you're doing it wrong. Imagine driving from traffic light to traffic light doing that. The person behind who speeds up and slows down more slowly will still be behind you at the next light, they'll just have spent far less getting there.
The most expensive metre you drive is always the first one when you start. It takes huge energy to get a car going. So if you can safely roll gradually up to a traffic light as it changes from red to green, without stopping, it is more efficient than stopping and restarting.
While putting the car into neutral and coasting may feel like you're using less fuel, it's dangerous – don't do it. You always need access to the accelerator to avoid unexpected hazards. Plus cars can handle far worse on sharp corners when in neutral.
In many ways, this all comes down to one little rule of thumb.
When you put your foot on the accelerator, the harder you press, the more fuel you use.
Just being conscious of this, and your road position, should massively increase how far you can drive on a tank of petrol.
While it's tricky to accurately gauge exactly how much you could save on fuel by making your car more fuel-efficient and driving more efficiently, the AA says when 50 of its staff undertook an eco-driving trial they saved an average of 10% in a week – the biggest saving was a whopping 33%.
On an overseas holiday I got to test this, thanks to a sexy little digital display in my hire car which gave me a km/litre readout. For every trip, I drove normally on the way there and used the 'think when pressing the pedal' method above on the way back.
If you're thinking 'did he really bother while on holiday?' – yes I did, and I loved it. Luckily my girlfriend (now my wife) is very understanding!
The improvement was enormous. Overall, I drove about 500 miles, and the different 'efficiency' averages per litre of petrol were incredible: for normal driving, it was 11.2km per litre, but for efficiency-conscious driving, a remarkable 13.4km per litre.
Most intriguingly, the efficient driving didn't cost me any time at all, and on motorways my top speed didn't change. Others drove harder, only to brake harder at the next traffic light...
- Martin Lewis, MSE founder & chair
Step 3: Find the cheapest petrol or diesel prices in your area
The easiest way to find the cheapest forecourt in your area for petrol, diesel, super unleaded or premium diesel is by comparing prices using a nifty free tool.
Go to website PetrolPrices.com and after registering, enter your postcode and tell it how far you're willing to travel for fuel (up to 20 miles) and what fuel type you're after. It'll list the cheapest filling stations in your area (it says the most up-to-date figures are displayed, which in practice seems to mean results are between one and four days old) and covers 8,500ish forecourts across the UK.
A quick check before you need to fill up could save you some decent cash (there's also a mobile app to make it easier to use on your phone). For a Durham postcode, the price of unleaded within a five-mile radius on Monday 17 January ranged from 141.9p/litre to 154.9p/litre. While the difference per litre may be pennies, in terms of percentage that's an increase of over 9%.
Also, keep an eye out for short-lived fuel discount promotions that pop up from time to time. There aren't currently any on that we know of, but we'll publish details here when there are.
Buying petrol is a regular outlay, and you spend more on it in a year than you think – £30 a week is over £1,500 a year. As many petrol stations (including the supermarket ones) run some form of loyalty scheme, it's worth signing up to schemes for the forecourts you'll use most regularly to get a little bit extra back.
However, never choose a petrol station just for its loyalty scheme, as the difference is small compared to petrol price variance (also see the Loyalty Points Boosting guide).
There are several other ways to cut the cost of petrol and diesel:
Then there's no panic and you've enough time to get to a cheaper petrol station. Leave it longer and you'll fill up at the next one you see, so you won't be focused on price.
This is slightly offset by the fact that a lighter car uses less fuel. But with 50 miles of fuel left, the difference is tiny.
Many petrol stations sell 'high performance' fuels, yet there's little or no performance difference for most non-performance cars. So only fill up with the super-fuels if you've a sports car or you've been specifically advised your car will actually use the petrol correctly.
The AA tells us that for most other cars, high performance fuels are too pricey for regular use. But if you're keen, it suggests using a high performance fuel every third or fourth tank full to keep the engine clean and efficient, then revert to normal fuel.
Talk of filling up at night getting you more is a slight urban myth, as the difference is minuscule – pennies at best. Fuel pumps are calibrated by volume, so fill up at night when it's colder and you get a tiny, tiny bit extra.
Filling your tank to the top isn't great, as it adds weight to the car (see how to make your car more fuel-efficient). But if you must, don't keep going after the petrol nozzle 'clunks'. If you do, you're overfilling.
Step 4: Pay using a cashback credit card
Cashback credit cards pay you back each time you spend on them. They are a great way to shave the cost of your fuel, but ALWAYS abide by the golden rule...
Set up a direct debit to repay the card in full each month, so you never pay interest, which would outstrip any gain.
The reason card companies offer cashback or reward schemes is simple. They want to encourage you to spend on the card and pay them interest. The interest cost of all cashback cards dwarfs the cashback you'll earn. For full details on what to consider before applying, see Credit card rewards.
Each time you apply for one of these cards, you'll be credit-checked by the lenders. Multiple applications in a short period can impact your future ability to get credit. Read full details in our Credit scores guide.
The easy way to pay off in full
It's easy to do this via direct debit, which allows the card company to take a variable monthly amount that corresponds with what you owe it. Sadly, some providers deliberately omit the 'pay off in full' option from direct debit forms, as it makes them less money. If that's the case, write 'pay off in full' on the form. They should honour it, but call up after a week or so to check they have.
You can get 5% bonus cashback on everything you buy, up to a maximum £100 with our top-pick American Express reward card. After the introductory bonus, cashback is then tiered up to 1%, though you need to spend £3,000+ a year to get any cashback.
Full details and more options in Credit card rewards.
Your successes using the five-step cheap petrol system
'Do it – you'll be surprised'
Thanks to driving tips from @MoneySavingExp, I have saved myself £20 in fuel in 1 month, driving more carefully. Do it, you'll be surprised.
- MoneySaver @mathewhasker on Twitter
'I doubled my fuel economy!'
Over the last 2 years I have almost doubled my fuel economy, without changing vehicles.
1. I drive much more smoothly and don't overtake other car users just to get one or two places further along in a big queue.
2. I leave for work a little later and return home a little later – as a result I no longer spend 30 mins plus on a 4 mile crawl through stop/start traffic on a 26 mile (each way) commute into and out of Aberdeen.
My blood pressure is also lower
'20 extra miles per tank!'
Results I've got from trying to drive more fuel-efficiently. Most of this has been city driving:
Previously, 33-35 litres gave me around 215 miles.
Driving more carefully increased this to around 235 miles.
Turning engine off at lights increased my mileage to 293 miles.
- MoneySaver Krishna
Once you've read the steps above, why not try the petrol/diesel diet? No, we don't advocate swigging the stuff – it's a challenge on the MSE Forum, where MoneySavers share tips to help cut their annual fuel spend, track savings and inspire others.
The forum's proved hugely powerful in the past, seeing people work together to get debt-free, pay off mortgages and more. It's free to join, and open to all – see the Petrol/diesel diet challenge discussion.
The savings from following our five-step system can be huge. For someone who drives 15,000 miles a year averaging 35 miles per gallon (12.4 km/L), just buying petrol at the average UK price would cost £2,835 annually as of January 2022. Cutting this by 25% could save £709/year.
To work out the initial approximate cost of running your car, Gov.uk has a fuel consumption search tool that will help you work out roughly how much it'll cost you to run your car (it's best for new cars). Motoring website Honest John also has a handy 'real MPG' section where drivers have reported the miles per gallon they actually get.
How does the cost of fuel break down?
Tax makes up a hefty portion of a litre's cost. The current fuel-duty rate for petrol and diesel is set at 57.95p/L, and you pay 24.27p/L VAT on petrol and 24.81p/L on diesel.
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