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Apple Watch One Number Service

Information about activation and plans

Apple Watch Series 3/ Apple Watch SE (1st generation)/ Apple Watch Ultra (GPS + Cellular) or later with WatchOS version 4.2.2 or later
iPhone 6 or later running iOS 11.2.5 or later, and the latest carrier settings (see below for instructions)
A csl cellular plan. See below for eligible plans

How to activate cellular service on Apple Watch  (GPS + Cellular)

Good news - your iPhone and Apple Watch (GPS + Cellular) will share the same phone number. So you won't have to get or remember another phone number.
  • Apple Watch (GPS + Cellular) has an eSIM (embedded SIM) in it so there's no need to get a SIM card or transfer the SIM from another device.
  • When you pair your Apple Watch to your iPhone, you will be prompted to set up cellular service and guided through a few simple steps.
  • Be sure to have your username/ID and password/code on hand.
  • If you don't see a plan during set up, contact us and we can help you find one that works for you.
  • If you choose not to set up cellular service during the initial Apple Watch set up process, you can always go back later to the Apple Watch app on your iPhone and select Cellular under My Watch to sign up.

1. What you need to get started with Apple Watch with Cellular

  • Compatible iPhone models includes iPhone 6 and newer models. Your iPhone needs to be on iOS (Version 11.2.5 or later). To check or download the latest software version on your iPhone, go to Settings > General > Software Update. You will also need the latest carrier settings. On your iPhone, tap Settings > General > About and follow the prompt to update to the latest carrier settings.
  • Your Apple Watch Series 3/ Apple Watch SE (1st generation)/ Apple Watch Ultra (GPS + Cellular) or later needs to be on WatchOS version 4.2.2 or later
  • An Eligible cellular service plan from csl
  • Your iPhone and Apple Watch must both use csl

2. How do I find out if my service plan is eligible to subscribe to the watch plan?

  • An eligible post-paid service plan is required on the iPhone that you want to use with your Apple Watch.
  • To check if your service plan is eligible, dial *163# using the iPhone that you want to use with your Apple Watch. You will receive an SMS with eligibility information.

3. How to subscribe and activate the service?

Set up mobile data on your Apple Watch with Cellular

When customer starts the Apple Watch One Number Service eSIM subscription process via the Watch app in iPhone, the system will check whether the customer has completed Real-name Registration. If not completed, the system will send the customer a text message. By clicking on the SMS link, customer can submit his/her identity documents to complete Real-name Registration, upon successful Real-name Registration, he/she can subscribe Apple Watch One Number Service eSIM immediately. If personal info needs updating before submitting Real-name Registration, review results will be sent by SMS or email within 3 working days. Please note you need to enter a one-time password to verify your identity as part of the self-subscription flow. For any enquiries, simply call our 24-hour Customer Service Hotline on 2512 3123.
Step 1:
From iPhone:
  1. Open 'Watch' app to pair your Apple Watch
  2. Tap 'My Watch' from bottom left of 'Watch' app
  3. Tap 'Mobile Data'
  4. Tap 'Set Up Mobile Data'
  5. Tap 'Select My Plan'
Step 2:
  1. Type in password of your mobile number
  2. Tap 'Login'
Step 3:
  1. Type in one-time password
  2. Tap“Submit”
Step 4:
  1. Select 'One Number Service@$18/month
  2. Read and accept the 'Terms and conditions'
  3. Tap 'Submit'
Step 5:
  1. Wait for the 'Activation done' message
  2. Tap 'OK' when finish'
Step 6:
  1. Return to the 'Watch' app
  2. If you see 1O1O / csl info icon next appears under DATA PLAN then your Apple Watch is successfully connected.

Wireless Network support

Apple Watch seamlessly connects to the cellular network whenever it's not connected to a nearby iPhone or Wi-Fi access point. Apple Watch (GPS + Cellular) supports voice and data over LTE.


Roaming outside your provider network coverage area is not available for Apple Watch (GPS + Cellular) even though your iPhone plan may support roaming. However, you will continue to be connected when your Apple Watch is in proximity of your iPhone or connected to Wi-Fi.
If your iPhone plan supports roaming, your caller will always hear the standard Hong Kong local connecting tone when you travel outside Hong Kong.
Learn more about Apple Watch at Visit for additional support.

Apple Watch One Number Service (“Service”) Terms and Conditions

  • In order to qualify for this service, you must subscribe to a designated csl / 1O1O mobile service plan (“Service Plan”), use an Apple Watch Series 3/ Apple Watch SE (1st generation)/ Apple Watch Ultra (GPS + Cellular) or later running on WatchOS version 4.2.2 or newer , and use a compatible iPhone 6 or later running on iOS 11.2.5 or newer.
  • Data usage of the Service will be deducted from the Service Plan of your iPhone.
  • You can make or receive calls from the Device using the mobile number of your iPhone.
  • HK$15 per month Service is applicable only to customers who subscribe to the Service for a commitment period of 24/36 months (the “Commitment Period”). The monthly fee of the Service for the first 6 months would be waived if customers port-in the numbers to csl and 1O1O for Service Plan subscription. After the Commitment Period, the Service will be automatically renewed on a monthly basis at HK$18 per month.
  • You can only use the Service with one Device at a time.  If you want to connect to another Device, you can connect your Device to the Service via “Watch” app on your iPhone.  Alternatively, you can purchase an additional Service to use with the new Device on your iPhone.  
  • If you have subscribed to Multi-User Service Plan (“MUP”) and activated six SIM cards (one primary SIM card and five secondary SIM cards), you can purchase a total of up to 4 Services under all the mobile numbers in your MUP.
  • The Service does not support international roaming.
  • If you terminate the Service Plan of your iPhone, you are required to terminate the Service of your Device by calling our customer service.
  • The Service is subject to the Mobile Service Agreement of CSL Mobile Limited, please visit
  • If there is any inconsistency between the Chinese and English versions of these terms and conditions, the English version shall prevail.

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