On 1 September the new registration lands and the plate reads 76. For anyone shopping for or sitting on a used EV, that date matters more than it looks — not because of the plate itself, but because of what it does to supply.

What Actually Happens in September

Plate-change months are the two busiest new-car periods of the year, and every new car delivered on a finance deal or a part-exchange displaces an older one. Those displaced cars don't vanish. They land on forecourts, in auction lanes and on classified sites over the following weeks.

For petrol and diesel that's an old, well-understood rhythm. For EVs it's newer and sharper, because the used EV parc is still small and growing quickly. A few thousand part-exchanged EVs makes a much bigger dent in a market this size than the equivalent would in the petrol market.

  • More choice, softer prices through September and into October, as part-exchanges work through the system
  • More competition if you're selling privately — your car is suddenly one of many, not one of a few
  • Wider quality spread, because a part-exchange is priced on age, mileage and condition, and nobody in that chain has measured the battery

If You're Selling — Move Before the Wave

The window that matters is roughly now until the end of August. Sell into a thin market and your car is the option; sell in late September and it's one of a dozen tabs someone has open.

The bigger problem is that a private EV sale stalls on one question, and it's always the same question: what's the battery like? Without an answer, the buyer prices in the worst case, and that discount comes off your asking price. With a certified State of Health figure, the question is answered before it's asked.

📋 Worth Knowing

A dashboard range estimate is not a battery report. It reflects recent driving and current conditions, not the actual condition of the pack. Neither is the manufacturer's own health readout — that's the car reporting on itself.

If You're Buying — the Choice Cuts Both Ways

More stock is genuinely good news. It also means more cars that have been through a part-exchange chain where nobody looked at the battery, and a wider range of condition hiding behind similar-looking adverts.

Two cars, same model, same year, same mileage, similar price. One at 96% State of Health, one at 84%. Nothing on the advert distinguishes them, and nothing you can check on a test drive will either. On a used EV, the battery is most of the value — that gap is thousands of pounds, and it's invisible.

  • Get the test before money changes hands, not after — a certificate on a car you've already bought is information, not leverage
  • Test at the seller's address so you're comparing the actual car, not a description of it
  • Treat a refusal as an answer. A seller with a healthy battery has no reason to object to it being measured

If You're Doing Neither

Plenty of people aren't buying or selling this autumn and still want to know where they stand. That's a reasonable thing to want — a State of Health figure now gives you a baseline, and the second test in a year or two tells you the rate of change, which is the number that actually predicts what your car will be worth when you do come to sell.

It also catches problems while they're still small. Cell-level faults and charging behaviour issues don't announce themselves on the dashboard, and they don't get cheaper to deal with by being left alone.

The Practical Version

  • Selling this autumn: get certified in August, list before the plate change, and put the certificate in the advert
  • Buying this autumn: shop in late September when choice peaks, and test before you commit
  • Neither: take a baseline now, so next year's number means something

Every one of those is the same test. An Aviloo certified State of Health check on your driveway or the seller's — the FLASH test takes minutes, the whole visit under an hour, £95 flat, certificate emailed before PAD leaves. Eligible EVs also come with the Aviloo Battery Warranty, £2,700 of protection that transfers with the car.