Your time as a permanent resident begins on the date you were granted permanent resident status. This date is on your Permanent Resident Card (also known as a green card). In the example below, the card holder has been a permanent resident since 8/21/07.
It's likely that your "resident since" date will be prior to the date that you received your actual green card. For example, if you were granted an immigrant visa at the U.S. embassy in your home country and the green card was mailed to you at your U.S. address, you'll notice that the date will be the actual grant date.
If you are applying based on five years as a permanent resident or based on three years as a permanent resident married to a U.S. citizen, you may use Form N-400 to apply for naturalization up to 90 days before you meet the “continuous residence” requirement. You must meet all the other requirements at the time that you file your application with USCIS.
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