This article explains how to change the mobile number associated with your Snapchat account on iPhone, iPad or Android.
Steps
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Step 1. Open Snapchat
The icon depicts a white ghost on a yellow background.
If you do not log in automatically, enter your username and password
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Step 2. Swipe down to open your profile
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Step 3. Tap ⚙️ at the top right to open the "Settings" menu
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Step 4. Tap Mobile Number
It is the fourth item on the menu.
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Step 5. Tap the phone number
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Step 6. Enter the new phone number
Snapchat won't share it with other users.
If you want your friends to add you to Snapchat via your phone number or by adding you to their contacts, check the "Allow others to find me using my phone number" box
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Step 7. Tap Verify
Snapchat will send you a verification code via text message or phone call.
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Step 8. Select how you want to receive the code
Tap "Send Message" to receive a text message or tap "Call me" if you prefer a phone call.
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Step 9. Enter the code by typing it in the spaces that appear within the application
Tap "Resend code" if you don't receive any messages or phone calls
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Step 10. Tap Back
This button looks like an arrow and is located at the top left. The phone number associated with Snapchat will be replaced with the one you entered.