Dial Assist is a feature on the iPhone designed to automatically append the correct international or local prefixes when dialing phone numbers. It helps simplify the process of making international calls by intelligently identifying the necessary country and area codes, ensuring that the phone connects without requiring manual intervention. This feature is particularly useful for individuals who frequently make calls to contacts across various countries and time zones.

When Dial Assist is enabled, it can add the correct prefix for international calls based on your current location. Disabling Dial Assist requires you to manually input the full phone number, including country codes, for international calls.

To enable or disable Dial Assist on an iPhone, follow these steps:

  1. Open the Settings app.
  2. Tap on Phone.
  3. Toggle the Dial Assist switch to on (enable) or off (disable).

Dial Assist can be a convenience for international callers, but it may also cause issues with saved contacts that already have country codes or when using calling cards, which may not be recognized by the feature.