How Much Does It Cost to Run a Used Electric Car?
If you are weighing up a used electric car, the running cost is usually the deciding factor. The purchase price is one thing, but what really matters is what the car costs you every week once it is on your drive. The honest answer is that a used EV is generally cheaper to run than an equivalent petrol car, but the size of the saving depends heavily on how and where you charge, and on one thing many buyers overlook entirely: the health of the battery.
This guide walks through the real running costs, keeps the numbers honest, and explains why the battery is the part of the sum you cannot see on a test drive.
Charging at home is where the savings live
The single biggest factor in your running costs is whether you can charge at home. If you have a driveway or a garage with a home charger, you charge overnight on a domestic electricity tariff, and this is where an EV pulls clearly ahead of petrol on cost per mile.
Many energy suppliers offer dedicated overnight EV tariffs with a cheap off-peak rate for a few hours in the middle of the night. Charging during that window is by far the cheapest way to fuel a car in the UK or Ireland today, and for most drivers it comfortably beats the cost of petrol per mile. We are staying away from quoting exact pence figures here, because electricity prices and tariffs change constantly and vary by supplier, but the direction of travel is consistent: home charging on an off-peak rate is where the meaningful saving comes from.
The practical takeaway is simple. If you can charge at home, a used EV is very likely to cut your fuel bill. If you cannot, the picture is more mixed, which brings us to public charging.
Public charging changes the maths
Public charging, especially rapid and ultra-rapid chargers on motorways and at forecourts, costs considerably more per unit than home electricity. Rely on public rapid charging for most of your miles and the running-cost advantage over petrol shrinks, and in some cases can close almost entirely.
This does not mean an EV is a bad choice if you cannot charge at home. Slower destination charging at work, supermarkets or on-street points is often cheaper than rapid charging, and many drivers mix sources. But it does mean you should be honest with yourself about how you will actually charge before you assume big savings. A buyer with a driveway and a mostly-local routine is in a very different position from someone doing long motorway runs and topping up on rapid chargers.
Servicing and maintenance are genuinely lower
Here the advantage is clearer and less dependent on your circumstances. An electric car has far fewer moving parts than a petrol or diesel. There is no oil to change, no spark plugs, no timing belt, no exhaust system, no clutch in the traditional sense, and far less to go wrong mechanically over time.
Regenerative braking also means the brake pads and discs tend to last longer than on a petrol car, because much of the slowing is done by the motor rather than friction. You still have tyres, wiper blades, cabin filters, brake fluid and the usual consumables, and tyres can wear a little faster given an EV's weight and instant torque, but the routine servicing bill is generally lower and simpler. For most owners this is a real, ongoing saving.
Insurance and road tax: the higher-level picture
Two costs are worth setting expectations on honestly.
Insurance for EVs has historically run a little higher than for comparable petrol cars, partly because repairs can be more specialised and partly because many EVs are quick and relatively heavy. It varies enormously by model, driver and postcode, so the only reliable approach is to get a real quote on the specific car you are considering before you commit. Do not assume the EV will be cheaper to insure.
On road tax, the long-standing exemption for electric cars has ended. Since April 2025 EVs in the UK pay Vehicle Excise Duty like other cars, and more expensive models can attract the additional premium supplement. It is no longer a zero, so factor it in, but for most mainstream used EVs it remains a modest annual cost rather than a dealbreaker. Ireland has its own separate motor tax rules for EVs, so check the local position for where the car will be registered.
The running cost most buyers forget: battery health
Here is the part that does not show up on any spec sheet or insurance quote. On a used EV, the condition of the battery quietly shapes your running costs every single day, and it is invisible on a test drive.
A healthy battery holds close to its original usable capacity, so you charge less often and get the miles you expect. A degraded battery holds less charge, which means more frequent charging, more time spent plugged in, and if you rely on any public charging, more of those pricier top-ups. The same journey costs you more, simply because the pack cannot store as much energy as it used to. Two identical cars on a forecourt, same age and mileage, can have meaningfully different real-world running costs purely because of how their batteries have aged. We cover the mechanics of this in why EVs deliver less range than advertised and in used EV battery degradation explained.
The trouble is that the dashboard range readout is an estimate, not a diagnosis. It cannot tell you the true state of health of the pack, and it certainly cannot tell you whether individual cells are weak. That uncertainty is the single biggest unknown in the running-cost sum, and it is the one thing a normal viewing cannot resolve.
How to remove the unknown before you buy
Everything else on this page you can estimate reasonably well in advance. You know whether you can charge at home. You can get an insurance quote. You can look up the VED band. The battery is the exception, and it happens to be the most expensive component in the car, with a replacement running into many thousands of pounds if it ever came to that.
This is why an independent battery health check is worth doing before money changes hands. An independent test measures the actual state of health of the pack and looks at it cell by cell, giving you a certified figure rather than a guess from the seller or the dashboard. It turns the biggest running-cost unknown into a known number, so you can judge whether the car in front of you will cost what you expect to run, or quietly cost more. You can read more about how the battery drives the whole ownership picture on our EV battery health hub.
Running a used EV can be genuinely cheaper than the petrol car it replaces, especially if you charge at home. Just make sure the battery underneath the price is as good as the badge suggests.
If you have a specific used EV in mind, book a £100 certified battery health test before you buy and get the one number the forecourt cannot give you.