Change your default sending address in Yahoo Mail
The default sending account is the email address that pre-populates as the "From" address when you create a new message. If you have an extra email address set up, or another email address linked to your Yahoo Mail account, you can choose one of them as your default sending address by following the steps below.
- Click the Settings menu icon | click More Settings .
- Click Writing email.
- In the Default sending address drop-down menu, select your preferred email address.