Phone works, the screen is smashed up, the screen even still works....

I probably already know the answer, however I am going to ask anyhow. Tripped and slammed the phone into concrete(yay!) and the screen is now cracked/smashed up. Everything on the phone works, I can even used the screen and call people everything. It's just cracked...I am guessing since I did not purchase insurance on the phone I'd have to pay full price for a new phone or I could replace the screen. My question is, since I got the phone as an upgrade for the $99 or something of the like would it be $199 to replace the phone or $99? And I guess I should ask if it's cheaper to replace the screen than the whole phone(which I am guessing so).