How to Clear Contacts on an iPhone
One of the most useful features on Apple's iPhone, the popular smartphone, is its ability to sync contact information with services like Microsoft's Outlook and Google's Gmail. This can save you a lot of time as an alternative to inputting all of the contacts manually. Contacts are then accessible on the iPhone itself by tapping on the "Contacts" icon. If you wish to clear all of the contacts on your iPhone, doing so is as simple as a few button clicks.
Things You'll Need
Connect your iPhone to your computer using the USB link cable that came with the device. Plug one end of the cable into any USB port that is available on your computer and the other end into the iPhone itself.
Open Apple's iTunes.
Click on the name of your iPhone under the "Devices" menu listing. This menu will appear on the left side of the main iTunes program window when your iPhone is connected. This will bring up the "Settings" page for your iPhone.
Click on the tab that reads "Info." It is toward the right side of the iPhone "Settings" page.
Click on the checked box next to the phrase "Sync Contacts" under this "Info" page. This will remove the check and effectively tell your iPhone that you no longer want to have contact information on your iPhone.
Press the "Sync" button in the lower right corner of the main iTunes program window. This will sync your iPhone with your iTunes library and save your new settings. Your iPhone will no longer be synced with any contact information, and all contacts will have been cleared from the iPhone.