Changing WhatsApp Number? Check These Things First

Before You Change Your Number
WhatsApp lets you move your account to a new phone number using Change Number. Make sure the new number can receive SMS or calls before starting the process.
Check Your Existing Number
Your old number must already be registered with WhatsApp before you begin. Check it under WhatsApp > Settings > your profile to confirm the registered number.
Some Numbers Aren’t Supported
WhatsApp does not support numbers such as VoIP, toll-free, premium-rate and personal numbers. Landline numbers can be used only with the WhatsApp Business app, according to WhatsApp’s guidance.
Change It From Your Phone
The Change Number feature works on your primary phone, not WhatsApp Web or Desktop. Go to Settings > Account > Change Number, then enter your old and new numbers in full international format.
Tell Your Contacts About the Change
WhatsApp lets you notify all contacts, recent contacts or selected contacts about your new number. Your group chats are notified automatically, even if you don't enable contact notifications.
Don’t Forget Your Chat Backup
A cloud backup is linked to the phone number used when the backup was created. WhatsApp recommends creating a new backup after changing your number to help prevent data loss.
Moving to a New Phone?
Change your WhatsApp number on the old phone first, then back up your chats using the new number. Install WhatsApp on the new phone, register the new number and restore the compatible backup.