Get higher voice quality with AT&T HD Voice

With AT&T HD Voice, you enjoy a higher level of voice quality when you make and receive calls. The key is wide-band audio technology and noise cancellation on our network. To get HD Voice, both calling parties must:

• Be in an HD Voice coverage area
• Use an HD Voice-capable smartphone
• Have AT&T PREPAID^SM or wireless service set up for HD Voice
• Have the HD Voice SIM card that came with the device

Good to know: Activate the SIM that comes with your new smartphone to make sure all supported features work properly. If you use another SIM with your HD Voice device, some phone features may not work.

SIM card compatibility
AT&T HD Voice requires a SIM card that is UICC-G or higher SIM card installed in your smartphone to enjoy the rich calling experience of AT&T HD Voice. Want to make sure to find out if your SIM card is HD Voice compatible? In the SIM card number, look for the digits 27 or higher in the 9th and 10th positions.

Don't have a compatible SIM card? Get one at an AT&T store.

Restrictions
Some features and services aren’t compatible with HD Voice, like:

• Voice dialing
• OfficeDirect and OfficeReach for business accounts

If you have an AT&T HD Voice smartphone and one of these incompatible features, you can choose between using HD Voice or the incompatible feature during the set-up process. We'll remove these features from your line once you add HD Voice.