How to Change Battery in Eufy Door Lock

This guide walks you through how to change the battery in a Eufy door lock with clear, simple steps. Whether you’re a first-time user or need a refresher, you’ll find everything you need to keep your smart lock running smoothly.

Key Takeaways

• Low battery alerts are your first clue: Eufy locks notify you via app or beeping sounds when power is low, giving you time to replace the battery before it dies completely.
• Use the right batteries: Most Eufy door locks require 4 AA alkaline batteries—avoid rechargeable or lithium types unless specified.
• Always turn off the lock before replacing: Press the power button or use the app to disable the lock to prevent accidental locking or electrical issues.
• Keep spare batteries handy: Store extra AA batteries near your lock so you’re never caught off guard by a sudden power loss.
• Test the lock after replacement: After installing new batteries, test both manual and app-based unlocking to ensure everything works correctly.
• Clean battery contacts during replacement: Wipe the battery tray and contacts with a dry cloth to prevent corrosion and ensure a strong connection.
• Know when to call support: If the lock still doesn’t work after battery replacement, check for firmware updates or contact Eufy customer service.

How to Change Battery in Eufy Door Lock

If you’ve ever been locked out because your smart door lock died, you know how frustrating it can be. The good news? Changing the battery in your Eufy door lock is simple, quick, and something you can do yourself in under 10 minutes. Whether you have a Eufy Smart Lock, Smart Lock Touch, or another model in the Eufy lineup, this guide will walk you through the entire process—step by step.

In this comprehensive how-to guide, you’ll learn exactly how to change the battery in your Eufy door lock safely and correctly. We’ll cover everything from recognizing low battery signs to installing new batteries and testing your lock afterward. You’ll also get practical tips to extend battery life and troubleshoot common issues. By the end, you’ll feel confident maintaining your smart lock like a pro.

Let’s get started!

Why Battery Maintenance Matters for Your Eufy Door Lock

Smart door locks like those from Eufy rely on battery power to function. Unlike traditional locks, they use electricity to power the motor that locks and unlocks the door, as well as the Bluetooth and Wi-Fi connections that let you control them from your phone. That means a dead battery doesn’t just mean inconvenience—it could mean being locked out of your own home.

Eufy designs its locks to give you plenty of warning before the battery dies. Most models will send a notification through the Eufy Security app when the battery level drops below 20%. You might also hear a series of beeps when you try to unlock the door, or see a flashing red light on the keypad. These are all signs that it’s time to change the battery.

Regular battery maintenance helps you avoid emergencies. By replacing batteries proactively—before they completely die—you ensure your lock stays functional and your home remains secure. Plus, knowing how to change the battery means you won’t have to wait for a technician or pay for a service call.

What You’ll Need Before You Start

Before you begin, gather the following items to make the process smooth and stress-free:

• 4 AA alkaline batteries: Most Eufy locks use standard AA batteries. Avoid rechargeable NiMH or lithium batteries unless your model specifically supports them—using the wrong type can damage the lock or reduce performance.
• A clean, dry cloth: This helps wipe down the battery compartment and contacts to prevent corrosion.
• Your smartphone with the Eufy Security app: Useful for checking battery status and disabling the lock remotely.
• A small flashlight (optional): Helps you see inside the battery compartment, especially if your lock is installed in a dimly lit area.
• A step stool or ladder (if needed): Some locks are installed high on the door, so make sure you can safely reach them.

Having these items ready saves time and prevents interruptions mid-process.

Step-by-Step Guide: How to Change Battery in Eufy Door Lock

Now that you’re prepared, let’s go through the actual process of changing the battery in your Eufy door lock. Follow these steps carefully to ensure a safe and successful replacement.

Step 1: Check the Battery Level

Before removing anything, confirm that the battery really needs replacing. Open the Eufy Security app on your phone and go to the device list. Find your door lock and tap on it. Look for the battery icon—it should show the current charge level.

If the battery is below 20%, you’ll likely see a warning message like “Low Battery” or “Replace Batteries Soon.” You might also notice that the lock responds more slowly than usual or that the keypad backlight is dim.

Alternatively, try unlocking the door using the keypad or app. If you hear three short beeps or see a red light flash, that’s another sign the battery is low.

Don’t wait until the lock stops working completely. Replacing the battery early prevents lockouts and keeps your home secure.

Step 2: Turn Off the Lock (Recommended)

For safety and to prevent accidental locking, it’s a good idea to disable the lock before changing the battery. You can do this in two ways:

• Using the app: Open the Eufy Security app, select your lock, and tap the power icon to turn it off. This disables the motor and prevents the lock from engaging while you’re working.
• Using the physical power button: Some Eufy models have a small power button on the interior side of the lock. Press and hold it for 3 seconds to turn off the lock.

Turning off the lock ensures that the mechanism doesn’t try to move while the battery is removed, which could cause damage or jam the system.

Step 3: Locate the Battery Compartment

The battery compartment is usually located on the interior (inside your home) side of the door lock. Look for a small panel or cover on the bottom or side of the lock housing.

On most Eufy models, such as the Smart Lock S280 or Smart Lock Touch, the battery cover is a rectangular plastic panel held in place by a small screw or a sliding latch. It’s often labeled with a battery icon or the word “Battery.”

If you’re unsure where it is, consult your user manual or check the Eufy website for your specific model. You can also search for “[Your Eufy Model] battery location” online for visual guides.

Step 4: Open the Battery Compartment

Once you’ve found the battery cover, it’s time to open it.

If your lock uses a screw:

• Use a small Phillips-head screwdriver to remove the screw.
• Set the screw aside in a safe place so you don’t lose it.
• Gently lift the cover off.

If your lock uses a sliding latch:

• Press the small tab or button on the side of the cover.
• Slide the cover downward or outward to release it.
• Lift the cover away from the lock.

Be careful not to force the cover. If it doesn’t open easily, double-check that you’ve released the latch or removed the screw completely.

Step 5: Remove the Old Batteries

Inside the compartment, you’ll see four AA batteries arranged in a row. They may be held in place by small clips or simply sit in slots.

To remove them:

• Gently push the batteries out from the positive (+) end using your fingers or a small tool.
• Pull them out one by one and place them in a recycling bin or battery disposal bag.
• Do not throw old batteries in the regular trash—alkaline batteries should be recycled to protect the environment.

Take a moment to inspect the battery contacts (the metal springs or plates at each end of the compartment). If you see any white powder or corrosion, wipe it away with a dry cloth. Corrosion can interfere with power delivery and cause the lock to malfunction.

Step 6: Insert the New Batteries

Now it’s time to install the new batteries. Here’s how to do it correctly:

• Take four fresh AA alkaline batteries.
• Check the polarity markings inside the compartment—each slot will have a “+” and “-” symbol.
• Insert each battery with the positive (+) end facing the correct direction.
• Push them firmly into place until they click or sit securely.

Double-check that all four batteries are inserted correctly. Reversing even one battery can prevent the lock from working or damage the circuitry.

Step 7: Close the Battery Compartment

Once the new batteries are in place, it’s time to close the compartment.

If you removed a screw:

• Align the cover with the lock housing.
• Press it into place and reinsert the screw.
• Tighten it gently—don’t over-tighten, as this can crack the plastic.

If you used a sliding latch:

• Slide the cover back into position until it clicks or locks.
• Give it a gentle tug to make sure it’s secure.

Make sure the cover is fully closed and flush with the lock body. An open or loose cover can let dust and moisture in, which may affect performance over time.

Step 8: Turn the Lock Back On

Now that the new batteries are installed, reactivate the lock.

If you turned it off via the app:

• Open the Eufy Security app.
• Select your lock and tap the power icon to turn it back on.

If you used the physical power button:

• Press and hold the power button for 3 seconds until you see a green light or hear a confirmation beep.

The lock should power up within a few seconds. You may see the keypad light up or hear a short startup sound.

Step 9: Test the Lock

Before you consider the job done, test the lock to make sure everything is working properly.

Try these methods:

• Manual unlock: Use the keypad to enter your code and unlock the door.
• App unlock: Open the Eufy app and tap the unlock button.
• Auto-lock feature: Walk away from the door and see if it locks automatically (if enabled).
• Physical key (if available): Test the emergency key to ensure the mechanical lock still works.

If the door unlocks smoothly and the app shows a green “Unlocked” status, you’re all set. If not, proceed to the troubleshooting section below.

Tips to Extend Battery Life

Replacing batteries is easy, but you can reduce how often you need to do it with a few smart habits:

• Avoid extreme temperatures: Heat and cold can drain batteries faster. If your lock is exposed to direct sunlight or freezing conditions, consider installing a weatherproof cover.
• Disable unused features: Features like auto-lock, voice alerts, or frequent app notifications use more power. Turn off what you don’t need.
• Update firmware regularly: Eufy releases updates that improve efficiency. Check the app for updates every few months.
• Use high-quality batteries: Cheap batteries may leak or die quickly. Stick with trusted brands like Duracell or Energizer.
• Check battery level monthly: Make it a habit to check the battery status in the app once a month, even if there’s no warning.

With these tips, your Eufy lock can run for 6 to 12 months on a single set of batteries—sometimes even longer.

Troubleshooting Common Issues

Even with careful installation, problems can occur. Here’s how to fix the most common issues after changing the battery:

Lock Doesn’t Power On

If the lock remains unresponsive after battery replacement:

• Double-check that all batteries are inserted correctly with the right polarity.
• Ensure the battery cover is fully closed and secure.
• Try reinserting the batteries to make sure they’re making good contact.
• If it still doesn’t work, try a different set of batteries to rule out defective ones.

App Shows “Low Battery” After Replacement

Sometimes the app doesn’t immediately recognize the new batteries. Try this:

• Restart the lock by turning it off and on again.
• Force-close the Eufy app and reopen it.
• Check for app or firmware updates.
• If the issue persists, contact Eufy support—the battery sensor may need recalibration.

Lock Beeps But Doesn’t Unlock

This could mean the motor is weak or the batteries aren’t providing enough power:

• Ensure you’re using alkaline batteries, not rechargeable.
• Check for obstructions in the lock mechanism.
• Try unlocking manually with the key to see if the issue is electrical or mechanical.

Battery Drains Too Fast

If your batteries die in just a few weeks:

• Check for firmware updates—older versions may have power bugs.
• Reduce the number of daily lock/unlock cycles if possible.
• Ensure the lock isn’t constantly searching for a Wi-Fi signal (weak signal = more power use).
• Consider switching to a model with a rechargeable battery if available.

When to Contact Eufy Support

Most battery issues can be resolved with the steps above. However, if your lock still doesn’t work after replacing the batteries correctly, it may be a hardware problem. Contact Eufy customer support if:

• The lock won’t power on even with new batteries.
• The keypad or motor is physically damaged.
• You suspect water damage or corrosion inside the lock.
• The app consistently shows errors unrelated to battery level.

Eufy offers excellent customer service and often provides troubleshooting guides or replacement parts under warranty.

Final Thoughts

Changing the battery in your Eufy door lock is a simple task that every homeowner should know how to do. With the right tools and a little patience, you can keep your smart lock running smoothly and avoid unexpected lockouts. Remember to check the battery level regularly, use high-quality alkaline batteries, and test the lock after replacement.

By following this guide, you’ve not only learned how to change the battery in your Eufy door lock—you’ve also gained the confidence to maintain your smart home devices like a pro. Stay proactive, stay prepared, and enjoy the peace of mind that comes with a reliable, secure entry system.