EV Battery Warranties Compared by Manufacturer

An EV battery warranty is the closest thing to a manufacturer publicly stating how confident they are in their own battery. The terms vary more than most buyers realise — not just in headline years, but in mileage caps and the minimum capacity a manufacturer actually guarantees. Here's how the real terms compare, and what actually matters when you're reading the fine print.

The Two-Tier Structure Almost Every Manufacturer Uses

Nearly every manufacturer splits EV warranty cover into two separate tiers. A shorter, broader vehicle warranty covers the car as a whole, similar to what you'd get on a petrol model. A longer, narrower battery and drive unit warranty covers specifically the pack and motor, and is usually the one that actually matters for long-term ownership. Both are capped by whichever limit is reached first, years or mileage, and the battery warranty almost always adds a minimum retention percentage: a guarantee that capacity won't drop below a stated share of the original before the manufacturer will repair or replace the pack.

Battery Warranties by Manufacturer (UK Baseline)

These are UK baseline figures for a representative spread of brands — Tesla's and Mercedes-Benz's battery mileage caps vary by specific model and variant, so treat the figures above as indicative rather than exact (marked with an asterisk). Terms also differ by market: US and EU buyers in particular should check their own region's terms rather than assuming the UK numbers apply, since several manufacturers offer different cover outside the UK.

Does the Warranty Transfer If You Buy the Car Used?

In most markets, yes — EV battery warranties are typically tied to the vehicle itself via its VIN, rather than to the original buyer, so remaining cover carries over to a second, third or later owner for whatever's left of the original term. This is one of the reasons verified remaining warranty coverage is such a meaningful factor in used EV pricing: two otherwise-identical cars can be worth noticeably different amounts depending on how much battery warranty term is actually left. A small number of manufacturers apply different terms for second owners, so it's worth confirming directly for higher-value purchases rather than assuming the standard terms above automatically apply.

What the Retention Percentage Actually Means

The retention percentage is the number that matters if you're worried about gradual capacity loss rather than an outright fault. Most mainstream brands settle around a 70% floor, meaning a capacity-loss claim only becomes valid once your battery has measurably dropped below 70% of its original capacity within the stated years and mileage. A handful of manufacturers, including some Lexus and Toyota terms, guarantee a higher 80% floor. Outright failure — the battery stops working entirely, or develops a fault — is typically covered for the full warranty term regardless of the retention percentage.

Why Mileage Caps Vary So Much Between Brands

A longer or more generous mileage cap doesn't necessarily mean a more durable battery — it more often reflects how a manufacturer prices in the risk of their specific chemistry and thermal management system, alongside how much they want to compete on ownership costs. A brand offering an 8-year/150,000-mile battery warranty isn't automatically building a better pack than one offering 8 years/100,000 miles; it may simply be pricing that risk differently, or targeting buyers who cover higher annual mileage. Real-world degradation data is a much better guide to how a specific model actually holds up than the warranty terms alone.

Warranty Terms Don't Tell You Today's Health

A warranty tells you what's contractually covered — it says nothing about the actual state of the battery sitting in front of you right now, especially on a used car. This matters most when you're buying second-hand: remaining warranty years and mileage are worth confirming, but they're not a substitute for an actual health check, particularly if a car is getting close to its warranty's mileage cap or retention threshold.

Warranty terms are also worth checking on their own merits before you buy, particularly for anyone planning to keep a car well past the typical ownership window. See exactly what's covered for your specific make, model and market with the checker below.