Behind the scenes
InformationalHow Refurbished Phones Are Tested and Certified
From IMEI verification to battery health — every step that turns a returned phone into a certified refurbished one.
The testing and certification process is what separates a quality refurbished phone from a risky used one. Here's a behind-the-scenes look at how phones are restored to like-new condition.
Step 1: Initial inspection
Each device is visually inspected for damage. Screens, frames, backs and ports are checked for cracks, dents or unusual wear.
Step 2: Functional testing
Every component is tested — including cameras, speakers, microphones, buttons, sensors, Wi-Fi, Bluetooth and cellular performance. Read our 90-point quality check explained.
Step 3: Battery health check
Battery capacity is measured. Anything below 85% is replaced with a new battery to ensure long-lasting performance.
Step 4: IMEI and software verification
The IMEI is checked against blacklists to ensure the phone isn't stolen or finance-locked. The phone is then factory reset and updated to the latest software.
Step 5: Final cleaning and grading
Each phone is thoroughly cleaned and assigned a grade (Pristine, Excellent, Good or Fair) based on cosmetic condition.
Step 6: Certification and packaging
Once certified, the phone is packaged with charging accessories and a warranty card. Browse certified devices on our main collection.
Frequently asked questions
How long does the refurbishment process take?
On average, 1-3 days per device, depending on whether parts need to be replaced.
Are original parts always used?
Quality refurbishers prioritise OEM parts but high-grade aftermarket parts may be used for non-critical components.
James Holloway
Technical Editor
Part of the Second Hand Phones editorial team — writing honest, useful guides for UK shoppers buying second-hand smartphones.
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