Personal | Business
Sign in or Register
O2 Logo White
  • Shop

    Phones

    • Phones
    • Upgrades
    • Apple iPhone
    • iPhone 16
    • Android phones
    • Refurbished phones

    Tablets, laptops and dongles

    • Tablets
    • Apple iPad
    • Android tablets
    • Laptops
    • Dongles and mobile WiFi

    SIMs and Tariffs

    • Pay Monthly SIMs
    • Pay As You Go SIMs
    • Tariffs
    • International
    • Top-up
    • Essential Plan

    Accessories and more

    • Tech and accessories
    • Apple Watch
    • Smartwatches
    • AirPods
    • Coming soon
    • Great deals
  • Why O2

    Flexibility

    • O2 Switch up
    • O2 custom plans
    • Multisave
    • O2 Recycle
    • Click and collect

    Perks

    • O2 Extras
    • Volt
    • Priority tickets and offers
    • Perks at O2 venues
    • Pay As You Go Rewards

    Services

    • Manage your account
    • Keeping kids safe online
    • Ideas and Inspiration
    • Insurance

    Connected

    • Coverage checker
    • Network coverage
    • 5G coverage
    • O2 WiFi
    • Using your phone abroad
    • Live bigger with Volt

      Discover extra benefits
    • O2 bubbles

      See all the reasons to choose O2

      Why join O2?
  • Help

    Help and support

    • Account
    • Products and services
    • Device guides
    • Network and international
    • Safety and security

    Most popular

    • Activating your SIM
    • eSIM
    • How to track your order
    • Payment support
    • Understanding your bill

    Useful links

    • Store locator
    • Network status
    • Faulty device
    • Virgin Media O2
    • Fraud help

    Contact us

    • O2 Community
    • My O2 App
    • Contact us
  • My O2
  • Search
  • Basket

Mobile security

Help and support

Each year, over 300,000 phones are reported lost or stolen in the UK. Over half of these phones are reported to not have password protection switched on. Meanwhile, the threat from viruses and malware is increasingly prevalent as more and more information is held on mobile phones. Mobiles can be an opportunity for criminals online and offline if users don't take precautions.

Getting protected

All the major software security companies such as Juniper and McAfee report increasing volumes of malware on mobile devices. Although Android devices were most at risk in the past, problems affecting Apple devices are reported.

As with PCs, there are antivirus and anti-malware products available. If you do download one of these, make sure it is from a well-known and reputable provider.

Secure your phone and SIM with a PIN

Putting a PIN on your phone means that if it is lost or stolen others will not be able to use it. For extra security, you can also set up a PIN on your SIM. A protected SIM can't be used by others if removed from your phone and put in another.

How to set up a SIM lock

Usually you find the SIM lock option under settings, phone or security, SIM lock. After turning on SIM security, you'll be prompted to enter your SIM PIN each time you start your phone or swap your SIM.

Note if you enter the PIN incorrectly three times, you may need to enter a personal unlocking key (PUK) to enable your SIM again. You can get your PUK going online to My O2. 

How to set up a phone PIN

To add a PIN to your phone, you can find this under settings, general or security and then passcode lock or screen lock depending on the type of phone you have.

I've lost my phone – what will you do to stop someone using it?

Once you report your phone lost or stolen we'll block the SIM. You must report a theft or lost phone immediately, as you're responsible for the cost of any calls, texts and data transfers made until it's blocked. We're open 24 hours a day, 7 days a week for reporting lost or stolen phones. You can get details of how to contact us here.

If you're not sure about any techy terms, check out our jargon buster

Last updated: 07/04/2025


Was this information helpful?


Can't find what you're looking for?

My O2

Track your usage, check your bills, upgrade and more

Go to My O2

Need help with your device?

Take a look at our useful self-help guide

Go to help

O2 Community

Head to our forum to ask questions and chat with other O2 customers

Join in
  • Find a store
  • Check our network
  • Sign in to My O2
  • Track my order
  • Search

Popular in shop

  • iPhone 16 Pro Max
  • iPhone 16 Pro
  • iPhone 16
  • Apple Watch Series 10
  • Apple iPad A16
  • Samsung Galaxy S25 Ultra
  • Samsung Galaxy S25
  • Samsung Galaxy Z Flip6
  • Google Pixel 9 Pro XL
  • Google Pixel 9 Pro
  • SIM Only Deals
  • Virgin Media broadband deals

Help and Support

  • Help home
  • Contact us
  • My O2
  • Collection and delivery

Shop

  • Phones
  • Tablets
  • Pay Monthly SIM
  • Collection and delivery
  • Virgin Media O2 Joint Venture
  • Facebook
  • Youtube
  • X
  • Instagram
  • About O2
  • Better Connections Plan
  • Careers
  • News & PR
  • Sponsorship
  • Virgin Media and O2
  • Accessibility
  • Terms & Conditions
  • Privacy policy
  • Cookie policy
  • Modern Slavery Statement

©2025 Telefonica UK Limited

In relation to consumer credit, Telefónica UK Limited is authorised and regulated by the Financial Conduct Authority (Reference Number 718822)

  • Home
  • Help
  • Safety and security
  • Device security
  • Mobile Security

Related pages

  • Mobile location services
  • Lost or Stolen Device

  • Help