On iPhone, visual voicemail lets you see a list of your messages and choose which ones to listen to or delete, without having to listen to instructions or prior messages.
NOTE: Visual voicemail may not be available in all regions, or may be an optional service. Contact your carrier for more information. If visual voicemail isn’t available, tap Voicemail and follow the voice prompts to retrieve your messages.
The first time you tap Voicemail, iPhone prompts you to create a voicemail password and record your voicemail greeting.
Tap Voicemail, tap Greeting, then tap Custom.
Tap Record when you’re ready to start.
When you finish, tap Stop. To review, tap Play.
To rerecord, repeat steps 2 and 3.
Tap Save.
Tap Voicemail, tap Greeting, then tap Default.
In Settings, choose Sounds and turn New Voicemail on. The alert sounds once for each new voicemail. If the Ring/Silent switch is off, iPhone won’t sound alerts.
In Settings, choose Phone > Change Voicemail Password.