Call me an idiot, but

<p>What does “zip+4 code of your permanent mailing address” mean? I put in my regular zip, and Common App had a fit. So…where do the other four numbers come in?</p>

<p>Nevermind, Wiki gave me the answer!</p>

<p>If anyone does not know their "zip +4", use the link below...</p>

<p>USPS</a> - ZIP Code Lookup - Search By Address </p>

<p>Hope everyone gets that app in on time!!!</p>