You have probably read that federal law requires every EV battery to be covered for 8 years or 100,000 miles, with at least 70% of its capacity guaranteed. Dozens of websites repeat it. We repeated it too, and we looked for the primary source and could not find one. This is the corrected version, and the real answer matters more to a buyer than the myth does.
Key Numbers at a Glance
- 8 years / 100,000 miles: the most common battery warranty among major brands, but it is a market habit, not a verified federal rule.
- 70% / 8 years / 100,000 miles: California’s adopted warranty rule for 2026-2030 model years (75% from 2031), but its legal footing is in dispute (see below).
- About 13 years: how long an average pack takes to fall to 70% at roughly 2.3% loss per year, which is longer than any warranty.
- 10 years / 100,000 miles: Hyundai, Kia and Genesis. 8 years / 175,000 miles: Rivian.
Short answer: An EV battery warranty is whatever your manufacturer’s written booklet says. Most major brands offer 8 years and 100,000 miles or better, usually guaranteeing a minimum capacity of around 70%. We could not verify a federal law requiring it, and California’s rule was caught up in a federal waiver fight. Read the booklet for your exact model year.
What the “Federal Law” Claim Gets Wrong
The 8-year, 100,000-mile figure is repeated by consumer sites, news segments and forum posts as federal law. When we looked for the actual regulation, we could not find wording that requires it for EV batteries. Owners who tried the same search on forums reported the same dead end: plenty of articles stating it, no regulation text. What does exist on the federal side is a proposal from the EPA to add battery durability and warranty requirements starting with model year 2027, including keeping 70% of usable energy at eight years or 100,000 miles. We did not find confirmation that it took effect as proposed, so treat it as a proposal until you see a final rule.
The reason the number feels like law is simple. Most manufacturers converged on it, and California adopted a similar rule. Both are real, but neither is the same thing as a federal guarantee.
What California Actually Adopted, and Why It’s Uncertain
California’s Advanced Clean Cars II rules do include a battery warranty. The regulatory text, summarised in CARB’s own rulemaking documents, requires manufacturers to warrant that defects will not drop the battery’s state of health below 70% for eight years or 100,000 miles on 2026-2030 model years, rising to 75% from the 2031 model year.
The complication is legal. Congress used the Congressional Review Act to rescind the federal waiver that let California enforce these rules, and the resolution was signed in June 2025. California and other states sued. A June 2026 legal summary describes the program as undergoing a regulatory revision while the challenge continues. The practical result: the 70%-for-8-years rule exists on paper, but you should not count on it as your legal protection. Your protection is the document the manufacturer gave you.
Three Warranties, Not One
| Warranty | Typical term | What it covers |
|---|---|---|
| Comprehensive (bumper-to-bumper) | 3-4 years / 36,000-50,000 miles | Most parts, including the 12V battery |
| Powertrain / drive unit | Often 5-8 years | Motor, inverter, related parts |
| High-voltage battery | Usually 8 years / 100,000 miles or more | Defects and, usually, a minimum capacity |
The battery warranty is its own contract with its own limits. A car can be out of comprehensive coverage and still be inside its battery warranty.
What Major Brands Offer
| Brand | Battery warranty | Capacity guarantee |
|---|---|---|
| Hyundai / Kia / Genesis | 10 years / 100,000 miles | Check booklet |
| Rivian | 8 years / 175,000 miles | Check booklet |
| Tesla Model S / X | 8 years / 150,000 miles | Check booklet |
| Tesla Model 3 / Y | 8 years / 100,000-120,000 miles depending on trim | Check booklet |
| Ford | 8 years / 100,000 miles | 70% |
| GM (Ultium) | 8 years / 100,000 miles | 70-75%, varies by model year |
Terms change by model year, trim and sometimes by owner. Some brands shorten coverage for later owners, so confirm it for the specific car, especially a used one. The calculator below uses your own numbers rather than ours.
Will a Normal Pack Ever Reach the Warranty Floor?
Almost never within the warranty period. Our degradation research puts the average loss at roughly 2.3% a year. At that pace a pack reaches 70% after about 13 years, which is well beyond every term in the table above. That is why battery claims are rare: the warranty mostly protects against defects and unusual failures, not normal ageing. If you want to know how your own pack is doing, our guide to checking EV battery health explains the options from free to paid.
When Does My Battery Warranty End?
What Can Void or Limit Coverage
- Physical damage or flood damage. A damaged pack is generally excluded. See our guide to EV flood and saltwater risk.
- Opening or modifying the pack. Opening the coolant reservoir or the battery enclosure can void coverage on some makes. Our battery maintenance guide explains what you should and should not touch.
- Heavy bidirectional use. Some brands cap how much you can use the car as a home power source. Ford's terms, for example, are reported to limit it to roughly 100 days a year, so read the booklet before relying on vehicle-to-home setups. Portable vehicle-to-load adapters are a lighter use but check the same section.
- Skipped software updates or service requirements. Keep proof of any required service.
- Fast charging is not an exclusion for the major brands we checked, though good habits still help. Our guide to battery preconditioning and fast charging covers the practical side.
The warranty usually runs from the date the car entered service, not from when you bought it, which matters on a used car.
If You're Buying Used
A used EV can be a good deal if the warranty is still running, because the largest repair risk, replacing the pack, is covered. Our used-EV buying checklist and our comparison of certified pre-owned programs show how to confirm what is left. If the warranty is close to expiring, a measured battery health reading before you buy is worth the cost, and the price of an out-of-warranty pack is in our battery replacement cost guide.
FAQ
Is an 8-year, 100,000-mile EV battery warranty required by federal law?
We could not verify that it is. Most manufacturers offer it, and California adopted a similar rule, but the claim of a federal mandate was not supported by any regulation text we found. Check your own booklet.
Does the warranty cover normal degradation?
Usually only if capacity drops below the stated floor within the term, often 70%. Normal gradual loss above that floor is not a warranty claim.
What happens when I hit the capacity floor?
The manufacturer will normally assess the pack and may repair or replace modules or the full pack. The exact process depends on the brand, and a documented health reading helps your case.
Does the warranty transfer if I sell the car?
Often yes, but some brands reduce coverage for later owners. Confirm it in writing for the specific vehicle.
Does the 12V battery count as the EV battery?
No. The small 12V battery is normally under the comprehensive warranty, not the high-voltage battery warranty.
The Bottom Line
Drop the "federal law" assumption and read the booklet. Look for four things: the years and miles, the capacity floor, the exclusions, and whether coverage transfers to a second owner. For most buyers the real risk is not hitting the floor within the term. It is buying a used car with the warranty about to expire.
Once the factory battery warranty expires, some owners consider a service contract instead — here is how to tell if an EV extended warranty is worth it.
About the author: Written by Shurah, who researches and writes independently on the real cost of EV ownership — charging, maintenance, and total cost of ownership — backed by primary data and original calculations rather than recycled lists.
