Quick answer: Before paying for a second-hand iPhone, confirm it reaches the "Hello" setup screen with no request for someone else's Apple Account (Activation Lock), check the IMEI against a stolen and blocked database, read Battery Health and Parts and Service History in Settings, confirm "No SIM restrictions" under Network Provider Lock, then test Face ID or Touch ID, cameras, speakers, microphones, True Tone and charging. Don't hand over money until every step passes.
This checklist is written for buying in person or checking a phone the day it arrives. Each step tells you where to look, what a good result looks like and which results should end the deal. Every setting path below was checked against Apple's UK support pages in October 2026.
Before you meet: what to ask the seller
Ask for the IMEI number, the exact model and storage, and whether the phone has been erased and removed from the seller's Apple Account. A seller who won't share the IMEI before you meet is a reason to walk away. You need the IMEI to run a stolen-phone check, and it's harmless for an honest seller to give out.
Also ask whether any parts have been replaced and whether the phone has had liquid damage. You'll verify the answers in the steps below, but a mismatch between what the seller says and what Settings shows is itself useful information. If you're buying from a private individual, remember that UK consumer protection is weaker than buying from a business: Citizens Advice notes that a private seller can't misdescribe an item but can leave information out. Our guide to refurbished vs used vs renewed phones explains the legal differences.
The 12-step second-hand iPhone checklist
Step 1: Check for Activation Lock
Answer first: Activation Lock is the most important check. A used iPhone still linked to the previous owner's Apple Account can't be set up by you, and Apple tells buyers not to take ownership of any used iPhone protected by Activation Lock. You need to see the "Hello" setup screen with no prompt for the previous owner's details.
How to check, following Apple's guidance:
- Turn the iPhone on and wake it.
- If you see a passcode lock screen or the Home Screen, the phone hasn't been erased. Ask the seller to erase it completely in front of you (Settings > General > Transfer or Reset iPhone > Erase All Content and Settings).
- If you see "iPhone Locked to Owner" (iOS 15 or later), the phone is protected by Activation Lock. Do not buy it.
- Once you reach the "Hello" screen, start setup. If you're asked for the previous owner's Apple Account email or password, the phone is still linked to their account.
What the result means: If the seller is present, they can enter their password and remove the phone. If they aren't present, Apple says the previous owner can remove the device from their account in a web browser. Never accept "I'll remove it later". If the seller can't do it there and then, you have no guarantee it will ever happen.
Note on Stolen Device Protection: If the seller has Stolen Device Protection turned on (iOS 17.3 and later), signing out of their Apple Account away from a familiar location requires Face ID or Touch ID, a one-hour security delay, then Face ID or Touch ID again. Allow time for this if you meet somewhere public, or ask the seller to sign out and erase the phone at home before you meet.
Step 2: Find the IMEI and serial number
On the iPhone, open Settings > General > About and scroll for the serial number and IMEI. Apple also notes the IMEI is printed on the SIM tray of some models and on the barcode label of the box. Check that the IMEI in Settings matches the one the seller gave you and, where present, the one on the SIM tray and box.
Red flag: an IMEI in Settings that doesn't match the tray or box. That can mean a swapped part, a replacement handset or a box that belongs to a different phone.
Step 3: Run a stolen and blocked IMEI check
Answer first: In the UK, the main paid check for used phones is CheckMEND, the buyer-facing service linked to Immobilise, which is connected to the police National Mobile Property Register. CheckMEND says its report shows whether a device is recorded as stolen, lost, subject to an insurance claim or blocked by a mobile network.
Enter the IMEI on checkmend.com before you pay. Immobilise itself is a free registration service for owners: it lets you record your own phone's details so police can identify it if it's recovered. It isn't a buyer's check, but registering your phone once you've bought it costs nothing.
What the result means: any record of theft, loss, an insurance claim or a network block means walk away. A network-blocked phone may not work on UK networks at all, and a phone reported stolen can be recovered by police.
Step 4: Confirm the model number
Go to Settings > General > About. Next to Model Number you'll see a part number. Tap it to reveal the model number, which starts with "A". Search that A-number on Apple's "Identify your iPhone model" page to confirm the phone is the model the seller claims.
Why it matters: Apple's own model list shows the same iPhone uses different model numbers in different countries and regions. A model number that maps to another region isn't automatically a problem, but it tells you the phone is imported. That can affect things like SIM tray support, since some recent iPhones sold in certain countries are eSIM-only and have no SIM tray at all.
Step 5: Check Battery Health
Answer first: Open Settings > Battery > Battery Health (Battery Health & Charging on some iOS versions). Maximum Capacity shows how much charge the battery holds compared with when it was new. Apple says iPhone 14 and earlier batteries are designed to keep 80% capacity at 500 full charge cycles, and iPhone 15 models and later at 1,000 cycles, under ideal conditions.
On iPhone 15 models and later with iOS 17.4 or later, the same screen also shows the cycle count, the battery's manufacture date and its first-use date. Use them: a low cycle count with a recent first-use date supports the seller's story of light use.
Messages to watch for:
- "Your battery is currently supporting normal peak performance": good.
- "Performance management has been applied…": the phone has shut down unexpectedly before and is being throttled.
- A message that the battery's health is significantly degraded: budget for a replacement.
- A message that iPhone can't verify the battery is an Apple battery: a third-party or unverifiable battery has been fitted.
Step 6: Read Parts and Service History
Answer first: With iOS 15.2 or later, Settings > General > About shows a Parts and Service History section if parts have been replaced. Apple lists which parts each model reports: iPhone 12 and later show battery, display, logic board, front camera and rear cameras; iPhone 11 shows battery and display; iPhone XR, XS, XS Max and SE (2nd and 3rd generation) show the battery only.
Labels you may see, as Apple describes them:
- Unknown: the part isn't an Apple part, isn't working as expected, or couldn't be verified.
- Used: the part was previously installed in another iPhone.
- Unverified: the logic board has been replaced and couldn't be verified, which can affect features such as Apple Pay.
- Finish Repair: calibration wasn't completed, and Face ID or Touch ID won't be available until it is.
What it means: if no section appears, Apple has no record of replaced parts. A replaced screen or battery isn't automatically a reason to walk away, but it should be reflected in the price and should match what the seller told you. Apple also notes that only the most recent service of a part appears. On iOS 15.1 or earlier, only "Unknown" parts are flagged.
Step 7: Check the network lock
Go to Settings > General > About. If "No SIM restrictions" appears next to Network Provider Lock, the iPhone is unlocked. Apple can't unlock an iPhone. Only the network that locked it can.
Ofcom banned UK mobile companies from selling locked handsets from 17 December 2021, but phones bought before then, or bought abroad, can still be locked. If you can, put your own SIM in (or set up your eSIM) and make a call before paying.
Step 8: Test Face ID or Touch ID
Set up Face ID (Settings > Face ID & Passcode) or Touch ID (Settings > Touch ID & Passcode) with your own face or fingerprint during the inspection, then lock and unlock several times. If enrolment fails or the option is greyed out, that's a hardware or repair problem. Apple notes that an incomplete repair calibration ("Finish Repair") makes Face ID or Touch ID unavailable.
Step 9: Check the display, including True Tone
- Open a plain white page and look for dead pixels, yellow or pink tints, uneven brightness and burn-in (faint ghost images of the keyboard or status bar on OLED models).
- Drag an app icon slowly across every part of the screen to find touch dead zones.
- Turn True Tone on and off in Settings > Display & Brightness, or by holding the brightness slider in Control Centre. If the True Tone option is missing on a model that should have it, the screen may have been replaced.
Apple lists possible issues with non-Apple replacement displays, including True Tone not working correctly, lost or degraded ambient light sensor performance, incorrect colour calibration, uneven brightness and lower maximum brightness.
Step 10: Test cameras, speakers and microphones
- Cameras: open the Camera app and switch through every lens (ultra wide, wide and telephoto where fitted) and the front camera. Tap to focus on something close. Watch for blur that won't clear, black screens on one lens, or rattling during stabilisation.
- Speakers: play audio at full volume. Listen for crackling, and check both the bottom speaker and the earpiece speaker (useful for stereo on models that have it).
- Microphones: record a short video with the front camera and a voice memo, then play both back. Make a test call if you have a SIM with you.
- Buttons and switches: press volume up and down, the side button and the Ring/Silent switch or Action button.
- Charging: plug in a cable and, if you have one, place the phone on a wireless charger. Check the port for debris or looseness.
- Connections: join Wi-Fi and turn on Bluetooth.
Step 11: Look for liquid and physical damage
Answer first: Most iPhones have a Liquid Contact Indicator (LCI). Apple says it's normally white or silver and turns fully red after contact with water or a liquid containing water. On iPhones with a SIM tray, it's visible in the SIM tray slot. Apple's warranty doesn't cover liquid damage.
Remove the SIM tray and shine a light into the slot. A red indicator is a strong reason to walk away or negotiate. Apple notes some models, including iPhone 14, 15 and 16 series phones sold in certain regions as eSIM-only, have no SIM tray and no externally visible LCI, so on those you'll rely on the other checks.
Also look for:
- A screen sitting proud of the frame, or a gap along one edge. This can indicate a swollen battery or a poorly fitted replacement screen.
- Misted or dusty camera lenses.
- Bent frames: lay the phone flat on a table and check it doesn't rock.
- Missing screws near the charging port on models that have them.
Step 12: Erase and set it up as yours before paying
Finish by erasing the phone (if it hasn't been already) and starting setup with your own Apple Account. Only pay once you're signed in to your account, the Network Provider Lock line reads "No SIM restrictions" and your SIM works. At that point, the phone is yours in every way that matters.
Skip the checklist: shop a tested refurbished iPhone 13 and see today's price →
Red flags that should end the deal
- "iPhone Locked to Owner" or any request for the previous owner's Apple Account.
- Seller refuses to share the IMEI or let you check Settings.
- CheckMEND shows stolen, lost, insurance claim or network-blocked.
- The IMEI in Settings doesn't match the SIM tray or box.
- "Unknown" display or battery parts that the seller didn't mention.
- A red Liquid Contact Indicator.
- Face ID or Touch ID won't enrol.
- Seller insists on bank transfer only and won't meet or offer returns.
Best place to buy a second-hand iPhone
There are four broad routes, and the right one depends on how much checking you want to do yourself.
| Where you buy | Your legal protection | Who does the checks | Typical warranty |
|---|---|---|---|
| Private seller | Goods must match the description (Sale of Goods Act 1979) | You | None |
| Independent refurbisher or shop | Consumer Rights Act 2015: satisfactory quality, fit for purpose, as described | The seller, then you | Varies; check length and exclusions |
| Amazon Renewed | Consumer Rights Act 2015 plus Amazon's commercial guarantee | An Amazon-qualified supplier | Amazon Renewed Guarantee: 1 year (third-party sellers) |
| Apple Certified Refurbished | Consumer Rights Act 2015 | Apple | Apple one-year limited warranty; new battery and outer shell |
Buying from a refurbisher that publishes its testing, grades and warranty removes several of the risks above. The Tech Gadgets tests, cleans and factory resets every phone, signs it out of the previous owner's account with Activation Lock off, and unlocks it for all UK networks. Product pages state at least 85% battery health on Like New, Excellent and Very Good grades, measured at dispatch. Refurbished iPhones come with a 12-month warranty covering manufacturing defects and functional faults (excluding physical or water damage, electrical damage and battery wear), plus 30-day returns. It's still worth running steps 5, 6 and 10 when your phone arrives, because checking costs nothing.
Best second-hand iPhone to buy
The best second-hand iPhone is the newest model your budget allows that still gets current iOS updates and passes every check above. Battery health and parts history matter more than one model generation. For model-by-model recommendations, see our best refurbished iPhone to buy in 2026, and for how cosmetic grades compare, read refurbished iPhone condition grades explained.
Shop all refurbished iPhones with a 12-month warranty →
Frequently asked questions
How do I know if a second-hand iPhone is stolen?
Get the IMEI from Settings > General > About and run it through CheckMEND, which reports whether a phone is recorded as stolen, lost, subject to an insurance claim or blocked by a network. Also make sure the phone isn't Activation Locked. A stolen iPhone is usually still locked to its owner's Apple Account.
Can Apple remove Activation Lock for me?
Don't buy a phone on that assumption. Apple tells buyers not to take ownership of a used iPhone protected by Activation Lock and says the previous owner must remove it, either by entering their password or by removing the device from their account in a web browser.
What battery health is acceptable on a used iPhone?
Apple designs iPhone 14 and earlier batteries to keep 80% capacity at 500 cycles and iPhone 15 and later at 1,000 cycles. A used iPhone with Maximum Capacity in the high 80s or above is in reasonable shape. Below 80%, factor in the cost of a new battery.
How can I tell if an iPhone screen has been replaced?
On iOS 15.2 or later, check Settings > General > About for Parts and Service History. iPhone 11 and later report the display. An "Unknown" display label means a non-Apple or unverifiable screen. A missing True Tone option on a model that supports it is another clue.
How do I check if an iPhone is unlocked?
Open Settings > General > About. If "No SIM restrictions" appears next to Network Provider Lock, the iPhone is unlocked. If it shows a network name instead, only that network can unlock it. Apple can't.
Is it safer to buy a refurbished iPhone than a used one?
Usually, yes. A business seller owes you Consumer Rights Act protection, and a refurbisher has already done the account, lock and function checks. A private sale gives you limited legal recourse. Whichever you choose, run the checks on arrival.
Can I check Activation Lock online with just the IMEI?
Apple's current Activation Lock guidance for buyers is to check the phone itself: turn it on and confirm you reach the "Hello" screen without being asked for the previous owner's Apple Account. Do the check in person rather than relying on a third-party website.