Most Fitbits cannot be opened and repaired by the user—the battery is sealed inside and not designed to be replaced at home
Fitbit devices are built as single units with the battery permanently attached to the circuit board and enclosed in a case that is not meant to come apart. Unlike some older fitness trackers or smartwatches, Fitbits do not have a removable back panel or user-accessible battery compartment. If you try to force one open, you will damage the waterproofing seal and likely break internal components.
The company does this intentionally: sealed batteries allow Fitbit to make devices thinner, lighter, and fully waterproof. The trade-off is that when the battery stops holding a charge—which typically happens after two to three years of daily use—you cannot straightforward swap it out yourself.
Key Takeaways
- Fitbit batteries are sealed inside the device and cannot be replaced by the user without breaking the waterproof casing.
- Most Fitbit models last two to three years before the battery begins to degrade and no longer holds a full charge.
- Fitbit offers a replacement service for devices still under warranty or for a flat fee if the device is out of warranty.
- If your device is several years old and out of warranty, buying a new Fitbit is usually cheaper than paying for a replacement.
- Some third-party repair shops claim to replace Fitbit batteries, but doing so voids the warranty and risks water damage.
What happens when a Fitbit battery degrades
A Fitbit battery degrades gradually. You will notice the device no longer lasts a full week on a single charge, or it shuts down unexpectedly even when the display shows battery remaining. Eventually it may not turn on at all, or it will only power on while plugged into the charger.
This is normal wear. Lithium batteries lose capacity over time with each charge cycle. There is no way to reverse this—no reset, no software update, no calibration step will restore a degraded battery to its original capacity. Once the battery can no longer hold enough charge to power the device through a normal day, replacement is the only solution.
Fitbit's official replacement options
Fitbit (now owned by Google) offers two paths. If your device is still covered by the one-year limited warranty and the battery failure is not due to physical damage or water exposure, Fitbit will replace the device at no cost. You contact their support team, describe the problem, and they send you a replacement unit. The process typically takes one to two weeks.
If your device is out of warranty, Fitbit offers a replacement service for a flat fee. The cost varies by model—older or less expensive models cost less to replace than newer premium models. You can check the exact price on Fitbit's support website by entering your device model. Fitbit ships you a replacement and you return the old one in the prepaid box they provide.
Why third-party battery replacement is risky
Some independent repair shops and online services advertise Fitbit battery replacement. They typically charge $40 to $80 plus shipping. However, opening a Fitbit requires prying apart the sealed case, which almost always damages the waterproof gasket. Even if the technician successfully replaces the battery, the device may no longer be water-resistant, and moisture can corrode the new battery and circuit board within weeks.
Third-party repair also voids any remaining warranty coverage. If something goes wrong after the repair, Fitbit will not help you. For most people, paying Fitbit's replacement fee is safer and often cheaper than risking a repair that leaves the device vulnerable to water damage.
When replacement makes sense versus buying new
The decision depends on how old your Fitbit is and what model you own. If your device is one to two years old and still under warranty, contact Fitbit support—replacement is free. If it is out of warranty but less than three years old, check Fitbit's replacement fee for your model. If the fee is less than half the current retail price of a new device with similar features, replacement is the better choice.
If your Fitbit is four or more years old, a replacement unit may cost nearly as much as a new current-generation model. In that case, buying new makes sense: you get a device with a fresh battery, current software, and a new warranty. Fitbit regularly releases updated models with better sensors and longer battery life, so an older device may not be worth the replacement cost anyway.
How to extend your current Fitbit's battery life
While you cannot replace the battery yourself, you can slow its degradation. Avoid leaving your Fitbit in direct sunlight for long periods or in very hot environments—heat accelerates battery aging. Charge it regularly rather than letting it fully drain; lithium batteries degrade faster if repeatedly drained to zero. If you will not wear the device for several weeks, store it with a partial charge (around 50 percent) rather than fully charged or fully drained.
These steps will not prevent eventual degradation, but they can add several months to the device's useful life. Once the battery no longer meets your needs, contact Fitbit support to explore your options.
Frequently Asked Questions
Can I take my Fitbit to a phone repair shop to have the battery replaced?
Some phone repair shops will attempt it, but opening a Fitbit damages the waterproof seal. The device may work briefly after repair but will likely fail within weeks due to moisture damage. Fitbit's official replacement service is safer and often cheaper.
What if my Fitbit is still under warranty but the battery is dead?
Contact Fitbit support through their website or app. Describe the battery problem and provide your device's serial number and proof of purchase if you have it. If the failure is not due to physical damage or water exposure, they will send you a replacement at no cost.
How much does Fitbit charge to replace an out-of-warranty device?
The fee varies by model. Visit Fitbit's support page, select your device model, and look for the replacement service option—the price will be listed there. Older or entry-level models typically cost $40 to $80 to replace, while premium models cost more.
Is there any way to reset a Fitbit battery to make it work longer?
No. A degraded lithium battery cannot be reset or recalibrated. Software updates and factory resets will not restore battery capacity. Once the battery no longer holds a charge, physical replacement is the only solution.
Should I buy a new Fitbit or pay for a replacement if my device is three years old?
Compare Fitbit's replacement fee for your model to the price of a new current-generation Fitbit with similar features. If replacement costs less than 40 to 50 percent of a new device, replacement is the better value. If they are close in price, new is better because you get updated sensors, software, and a fresh warranty.