What Counts as Normal Tesla Battery Degradation by Mileage and Year
Use the free tool — BatteryCheck
Why this feels confusing
You look at the rated range your car shows now, compare it to the rated range when the car was new, and the number is lower. That is expected on any lithium-ion battery. The hard part is knowing whether the drop you see is normal for your mileage and year, or whether it is enough to matter. This guide only uses what is known about the warranty terms. It does not invent specific "normal" percentages beyond that.
The 8-year / 70% retention battery warranty
Tesla's battery warranty is described as an 8-year, 70%-retention warranty. In plain terms, this generally means the battery is covered for degradation issues for a set number of years, tied to a minimum capacity retention level, until whichever comes first between the years or an associated mileage limit set by the specific vehicle policy.
- Always confirm the exact years and mileage cap that apply to your specific vehicle and purchase date directly with Tesla or your warranty paperwork.
- The 70% figure is a retention threshold, not a prediction of how much range you should expect to lose by a certain year.
What counts as "normal" degradation
There is no single normal degradation curve that applies to every car, every year, and every mileage. What matters most is:
- Your car's rated range when it was new.
- Your car's rated range right now.
- Your current mileage.
- Your model and year.
Comparing these four numbers from your own car is the honest starting point. Without your specific numbers, no guide can tell you whether your degradation is normal or worth a service case.
How to check your own numbers
Write down or type exactly what your car's screen shows: rated range now, rated range when new (if known), current mileage, model, and year. If you already have a service estimate from Tesla, that document also contains real numbers worth reviewing line by line.
- Do not guess at numbers you don't have — leave them blank instead.
- Keep dates, mileage, and range figures together so they can be compared side by side.
Opening a service case that gets taken seriously
Being specific helps. A service case built around your actual rated range, actual mileage, and actual dates is easier for a service advisor to evaluate than a general complaint about "less range than before." Bring your numbers, and be ready to reference the 8-year/70% warranty terms as they apply to your vehicle.
This guide is not a diagnosis and is not affiliated with Tesla. Always confirm warranty terms, mileage caps, and service outcomes directly with Tesla.
What to do next
The free BatteryCheck tool reads the numbers you type — rated range now versus new, mileage, year, and model — or a service estimate you paste in. It works from your own document and your own numbers, not from assumptions. Use it to see the degradation math for your specific car before you contact service.