How do I stop IE11 suggesting sites?

Solution 1:

1. Open the Internet Options dialog.

   

2. Go to the Content tab and click the Settings button in the AutoComplete section.

   

3. Uncheck Suggesting URLs and confirm the dialog.

   

Solution 2:

Edit OP forgot to define OS at first, so this is for Windows 8 and will not help with Windows 7 :)

I think you need too turn off Enhanced suggestions

From the Start screen, tap or click Internet Explorer to open Internet Explorer.

Swipe in from the right edge of the screen, then tap Settings.
(If you're using a mouse, point to the bottom-right corner of the screen, move the mouse pointer up, then click Settings.)

Tap or click Privacy and turn Show enhanced suggestions as you type to Off.

Source and details about Auto Searching as well