5 THINGS TO CHECK BEFORE BUYING A USED PHONE
Buying a used smartphone can be a smart way to save money. With the prices of brand-new flagship phones continuing to rise, many people are choosing high-quality second-hand devices instead.
A used phone can give you excellent performance, a great camera, and premium features for a fraction of the original price. However, buying a second-hand phone also comes with risks.
If you are not careful, you could end up spending your hard-earned money on a stolen, blacklisted, damaged, or permanently locked device.
Before handing over your money, here are 5 important things you should always check before buying a used phone.
1. CHECK THE IMEI STATUS
The first and most important thing to check is the phone's IMEI number.
IMEI stands for International Mobile Equipment Identity. Every mobile phone has its own unique identification number.
If a phone has been reported as stolen or lost, its IMEI may be blacklisted by a mobile network. This can prevent the phone from connecting properly to cellular networks.
What to do:
Dial:
*#06#
The phone should display its IMEI number on the screen.
You can also find the IMEI number in the phone's settings or sometimes on the original box.
Before buying the phone:
- Check that the IMEI matches the phone and its packaging where applicable.
- Ask the seller where the phone came from.
- Be suspicious if the seller refuses to provide the IMEI.
- Check with your mobile network provider or a reputable IMEI checking service where available.
🚨 Important: If the phone appears suspicious, has an altered IMEI, or has been reported as stolen, do not buy it.
2. CHECK FOR WATER OR LIQUID DAMAGE
Water damage can cause serious problems inside a smartphone.
Even if the phone appears to work perfectly when you first test it, internal corrosion caused by moisture can lead to problems days or weeks later.
The phone could suddenly develop issues such as:
- Charging problems
- Poor sound quality
- Camera failure
- Screen problems
- Random shutdowns
- Complete failure
What to do:
Remove the SIM card tray and carefully inspect the area with a flashlight.
Some phones have a Liquid Damage Indicator (LDI) that changes colour when exposed to liquid.
However, the exact location and colour of the indicator can vary depending on the phone manufacturer and model.
Also check for:
- Rust around charging ports
- Corrosion inside the SIM tray
- Moisture under the camera lens
- Foggy camera lenses
- Unusual stains or marks
🚨 Take note : If you see signs of water damage, it is usually safer to avoid buying the phone.
3. CHECK THE BATTERY HEALTH
A phone's battery naturally becomes weaker over time. After years of daily charging and use, a battery may no longer hold a charge properly.
This means you could buy a phone cheaply but later spend extra money replacing the battery.
For iPhone users:
Go to:
Settings → Battery → Battery Health & Charging
Check the Maximum Capacity percentage.
A higher percentage generally means the battery can hold more of its original charge.
For Android users:
Battery health information varies depending on the manufacturer.
You can:
- Check battery information in Settings
- Use the phone's built-in diagnostic tools
- Check the manufacturer's official diagnostic application where available
- Use a reputable battery monitoring app
Before buying the phone, also test how quickly the battery drops while using:
- YouTube
- The camera
- Mobile data
- Wi-Fi
- Games
🚨 Tip: A phone that loses battery power extremely quickly may need a battery replacement soon.
4. CHECK THE SCREEN AND TOUCH SENSITIVITY
The screen is one of the most expensive parts of a smartphone to repair.
A damaged display can cost a significant amount of money to replace, especially on premium phones.
Many modern smartphones use OLED displays. Over time, some OLED screens can develop burn-in.
Burn-in happens when faint images, icons, or navigation bars remain permanently visible on the screen.
What to do:
Open a completely white image or webpage.
Look carefully for:
- Faint icons
- Ghost images
- Dark patches
- Strange colours
- Uneven brightness
- Lines on the display
Next, test the touchscreen.
Open a drawing or note-taking application and draw lines across the entire screen.
Make sure the touch screen works properly in:
- All four corners
- The centre
- The top and bottom edges
- Every area of the display
Also test:
- Brightness
- Auto-brightness
- Face ID or fingerprint scanner
- Screen rotation
🚨 Warning: If part of the screen does not respond to touch, you may be facing an expensive repair.
5. CHECK FOR ACCOUNT LOCKS (FRP AND ACTIVATION LOCK)
This is one of the biggest traps when buying a used smartphone.
A phone may look completely normal but still be linked to the previous owner's account.
For Apple devices, this can involve Activation Lock.
For Android devices, this may involve Factory Reset Protection (FRP).
If the previous owner has not properly removed their account, the phone could become locked after it is reset.
What to do:
Before paying for the phone, ask the seller to:
- Unlock the phone completely
- Show you the main home screen
- Open the settings
- Check the accounts connected to the phone
- Remove their personal accounts where appropriate
- Demonstrate that the device is ready for a new owner
Do not rely only on a seller saying:
"Don't worry, it works."
Test everything yourself.
🚨 Important: Never buy a phone if the seller cannot demonstrate that they legitimately own it and can properly transfer it to you.
BONUS: TEST THE IMPORTANT FEATURES
Before buying a used phone, take a few extra minutes to test the important hardware.
Check the following:
📷 Camera
Open both the front and rear cameras.
Take photos and videos.
Check whether:
- The camera focuses properly
- The image is clear
- Flash works
- Video recording works
🔊 Speakers
Play music or a video.
Listen for:
- Low volume
- Distortion
- Crackling sounds
🎤 Microphone
Record your voice and play it back.
Make sure the microphone works clearly.
🔌 Charging Port
Connect a charger and check whether the phone charges normally.
A loose charging port could require repairs.
📶 Network and Wi-Fi
Test:
- SIM card detection
- Mobile network
- Wi-Fi
- Bluetooth
🔘 Buttons
Test every physical button, including:
- Power button
- Volume buttons
- Silent switch where applicable
🔐 Biometrics
Test:
- Fingerprint scanner
- Face unlock
- Face ID where applicable
FINAL THOUGHTS
Buying a used phone can save you a lot of money, but only if you take the time to inspect the device properly.
Never allow a seller to rush you.
Take your time and check:
✅ IMEI and device identity
✅ Signs of water damage
✅ Battery condition
✅ Screen and touch sensitivity
✅ Account locks
✅ Camera and speakers
✅ Charging port
✅ Network connectivity
✅ Fingerprint or face unlock
If something feels suspicious, walk away.
There will always be another phone available, but recovering money from a bad purchase can be difficult.
A few minutes of careful checking can save you from wasting hundreds of dollars.
QUICK CHECKLIST BEFORE BUYING A USED PHONE
Before you pay, make sure you have checked:
☐ IMEI number
☐ Phone ownership and legitimacy
☐ Screen condition
☐ Touch sensitivity
☐ Battery condition
☐ Charging port
☐ Cameras
☐ Speakers
☐ Microphone
☐ Wi-Fi and Bluetooth
☐ SIM and network connection
☐ Fingerprint or Face Unlock
☐ Previous accounts removed
☐ No suspicious locks or warnings
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