With the price of filling an average car increasing by almost c.15% in March, I decided to take a look at how much getting your fuel from Costco could save you.
Now firstly, let me call out that, unlike a supermarket or petrol station, not everyone can just go to Costco and fill up. You need to be a member, and eligibility is typically limited to certain sectors such as banking, finance, local government, the Post Office, education, and others. It’s worth checking the latest details before applying (for example, via their Gold Star Membership information page).
There are multiple types of membership, but for this article I’m going to focus on the basic Gold Star Membership, which costs £42 a year, as the aim is to understand fuel savings alone. The Executive Membership costs double at £84 and offers no additional benefits in relation to fuel. Its main advantage is 2% cashback on most Costco purchases, although importantly this excludes fuel — something I’ll cover in more detail in a future article.
When writing this article I sampled fuel prices, which can be seen in the image below, and it makes for fairly eye-watering reading — especially when you consider how much lower they were only a month before. The speed at which prices have climbed really brings into focus just how volatile fuel costs can be, and how quickly everyday expenses can creep up without you fully noticing. It’s this sharp increase, even over such a short period of time, that prompted me to take a closer look at whether there are any simple, practical ways to offset some of that extra cost.
But how much fuel does an average car actually take? This depends on the size of your car and is a really important question when figuring out your potential savings. To help you I’ve included created three broad categories of car, small, medium and large and I’ve focused now on standard unleaded. For a small car that takes about 30 litres, you would save £2.10 per tank, Medium with a 52 litre tank you’d save £3.64 and a Large with an 80 litre tank you’d save £5.60.
So now it’s time to do the maths — is it worth joining Costco purely for the fuel savings?
As you can see from the images, there are two key considerations: firstly, the size of your car, and secondly, how often you fill up. What this really shows is that the savings are there, but they’re not automatic.
If you drive a smaller car, you’ll need to be filling up regularly (around every couple of weeks) before you start to break even on the membership cost. For medium-sized cars, the break-even point is more achievable for the average driver, while larger SUVs benefit the most, requiring fewer fill-ups across the year to make the membership worthwhile.
In simple terms, the more fuel you use, the quicker you benefit.
However, it’s also important to factor in convenience. Costco petrol stations are not as widely available as traditional fuel stations, so any savings need to be weighed against the extra travel time required.
Overall, if you’re already eligible for Costco and have a nearby location, the fuel savings alone can justify the £42 membership — particularly for medium and larger vehicles. For lighter drivers or those with smaller cars, the savings are still possible, but you’ll need to be more consistent with where you fill up to make it worthwhile.
As with most things when it comes to saving money, the key is simple: consistency.
