- Navigate to the Online Dashboard.
- Click your avatar in the top right corner and click Settings.
- Select a user.
- Update your email address in the field 'Email'.
- Click Save at the top right of the page.
https://support.withings.com/hc/en-us/sections/6216071736593-Withings-Web-App
https://support.withings.com/hc/en-us/sections/200352996-First-Steps