Anyone who drives will have noticed the gradual creeping up of petrol prices.
Prices at the pumps are actually at their highest since November 2014, with the average price last week 122.4p per litre, going as high as 150p per litre in some parts of the country.
So it goes without saying that saving money on petrol is a good thing. Or at least it should.
I’ve wondered for ages just how much difference a few pennies per litre makes to my wallet. Is it really worth spending the time tracking down the cheapest petrol stations and going out of your way to fill up there?
Watch me talk about petrol prices on Shop Smart Save Money in June 2018
The cost of filling up our car
We have a Ford Fiesta, which according to the book has a fuel tank capacity of 42 litres.
On current average prices it’d cost a huge £51.41 if the tank was completely empty (though of course it rarely is).
And every penny difference in the price of a litre adds up 42p per full tank. That doesn’t feel like much money to faff around trying to find cheaper petrol.
We don’t drive every day (we’re in London so use the Tube instead), but when we do need to fill up we tend to go to one nearby particular petrol station which is usually cheaper than the others close by and almost always on a route we take. That currently sells at an above average 122.9 per litre.
I took a quick look at websites which help you find the cheapest petrol near you (more on these and other tools below). The cheapest was 117.9p per litre, and would total £49.52. That’s a huge 5p less per litre, and £2 less overall for a tank.
Except that cheap fuel is 2.5miles away. And not on a route we ever take. So is it worth it to go out of the way?
A quick google and I got a figure of 47 miles per gallon for the average “real” MPG (Miles Per Gallon) for our car. Let’s assume that’s right.
So to go 2.5 miles it’d cost 29p (based on 117.9p). But that 2.5 miles is as the crow flies, not via actual roads. The real distance is 4.6 miles, which costs 52p.
Plus since it’s not on a route we’d normally take, let’s say it’s really an extra 8 miles as we’d need to come back on ourselves. So that’s 91p for the journey.
And the money saved in petrol, if it’s an empty tank, is £2. But we won’t be running on fumes. I’m going to assume we’ve a quarter of a tank still, meaning the real saving at the pumps is £1.50.
So really what we’d save is 59p, not taking into account the extra time it’s taken (maybe 20 minutes) or other car related costs.
Doesn’t seem worth it does it?
When it is worth going to a cheaper petrol station
Of course the actual saving you can make does depend on a few factors.
First if the cheaper station is on your way then the using it is a no brainer. And if you’re a regular on the same route you’ll get to know what stations are where and how they compare.
And if you’re out in the sticks then you will pay more locally so it could even be worth driving well out of your way to fill up.
It also depends your fuel consumption. The more petrol you use, the more money you’ll save. Even very small savings each time you get petrol can make a big difference over a year.
If you don’t think a small saving is worth it, don’t just wait until you’re nearly empty. Avoid motorway service station if you can. Supermarkets tend to have the lowest prices.
If you have to get some petrol at a very expensive petrol station, remember you don’t have to fill up. Just put in enough to get you home (and a bit more), then fill up the rest when you see cheaper pumps.
And don’t forget to look at both sides of the road. It always amazes me how petrol stations on opposites sides of the same road can sometimes have massive differences in price per litre.
What’s the size of your fuel tank?
If you want to work out the difference a penny at the pumps makes, it helps to know the size of your fuel tank. Here are the average figures, and some example prices to fill a tank from empty.
Small car – 40 litres
£1.20 per litre is £48 to fill up
Medium car – 55 litres
£1.20 per litre = £66.00 to fill up
Large car – 65 litres
£1.20 per litre = £78 to fill up
You can use the BBC fuel price calculator to work out exactly how much it’s cost. You’ll also see a comparison to the rest of the UK and selected other countries for what you pay.
Another useful tool is the fuel economy calculator. This calculator can work out a journey cost, how much fuel you’ll need for a journey and the real-life MPG.
How to find the cheapest petrol near you
There are a couple of websites which compare the prices of petrol based on whatever postcode you enter.
Annoyingly they provide the cheapest within five miles, which may not include the ones nearest to you or on your route.
A completely free service which covers 83% of petrol stations. You can expand your search to a 25 mile radius. As standard you get five searches per month.
You get 20 searches per week if you register, with five results per search.
You have to register to use this, and the free version gives 20 searches with five results.
For £2 a month (£20 a year) you get 100 searches a month, with 10 results per search. You can also sort by the nearest stations and limit the radius to two miles.
There’s a good offer to get 50% off if you’re over 60. This makes it £10 for a year. You need to enter your driving licence info for validation. There’s also a 50% discount if you have a Blue Badge, and 30% off for emergency services staff or members of the armed forces.