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7 mins read | Jun 30, 2026
Form I-551 is the official name for the green card, the document that proves you're a lawful permanent resident of the United States. The term often confuses people because it shows up in two places: it's the form number printed on the card itself, and it's also the name of a temporary stamp that USCIS places in your passport when the physical card isn't available. This guide clears up the difference and explains when you'd receive each one.
If you've heard someone mention an "I-551 stamp" or an "ADIT stamp," they're talking about that temporary proof of status, not the plastic card. Knowing which is which matters when you need to travel, start a job, or prove you're a permanent resident while you wait for a new card.
What is Form I-551?
Form I-551 is the formal designation of the Permanent Resident Card, the document most people simply call a green card. When USCIS approves your permanent residence, the card it issues carries the "I-551" label, and that card is your primary evidence of lawful permanent resident status.
As a permanent resident, you use the green card to prove you can live and work in the United States indefinitely. Employers accept it for work authorization, and you present it when you re-enter the country after travel abroad. The card is normally valid for ten years, after which you renew it on Form I-90, a process covered in our guide to renewing your green card and on the official USCIS Form I-90 page.
So when a form or an officer refers to "Form I-551," they usually mean the green card in your wallet. The complication is that the same number also names a temporary alternative to that card.
Form I-551 vs the I-551 stamp (ADIT stamp)
The I-551 stamp, also called the ADIT stamp, is temporary evidence of permanent resident status that USCIS places in your passport when you don't have a physical green card in hand. ADIT stands for Alien Documentation, Identification and Telecommunication, the system the stamp comes from, but for practical purposes it's simply a stand-in for the card.
The stamp proves the same status the card does, just for a limited time. It confirms you're a lawful permanent resident so you can keep working and traveling while you wait for the actual card to be produced or replaced. Functionally, the green card and the I-551 stamp carry the same weight as proof of status, with the key difference being that the stamp is temporary.
| Permanent Resident Card (green card) | I-551 stamp (ADIT stamp) | |
|---|---|---|
| Format | Physical plastic card | Stamp placed in your passport |
| Validity | Usually 10 years | Temporary, typically up to one year |
| When you get it | When permanent residence is granted or renewed | When the card is unavailable or delayed |
| Proves LPR status | Yes | Yes |
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When you receive an I-551 stamp
USCIS issues an I-551 stamp whenever you need to prove permanent resident status but don't have a usable card. The most common situation is a gap between losing access to your card and receiving a new one, since card production and delivery take time even after your status is secure.
You might receive the stamp in several scenarios. New permanent residents sometimes get one if their card is delayed in production. People renewing or replacing a card may need interim proof while the new card is printed, which can matter if the wait runs long; our overview of green card renewal processing time explains those timelines. The stamp also helps if your card is lost, stolen, or damaged and you have travel or work obligations before a replacement arrives.
To get the stamp, you typically request an appointment with USCIS and bring your passport, evidence of your filing, and identification. An officer then places the stamp in your passport, giving you a document you can show an employer or a border officer in place of the card.
How long the I-551 stamp is valid
The I-551 stamp is temporary and is usually issued with a validity of up to one year, unlike the green card's standard ten-year term. The exact period printed on the stamp depends on your circumstances and what USCIS expects your card timeline to be, so always check the date written on the stamp itself.
Because it expires, the stamp is meant to bridge a gap rather than replace the card permanently. If your new card hasn't arrived by the time the stamp nears expiration, you can request another one to maintain continuous proof of status. Keeping that proof current is important, since lawful permanent residents are expected to be able to demonstrate their status when traveling or verifying employment.
It's worth confirming the most current rules directly, since USCIS periodically adjusts how it issues interim proof and may instead extend a card's validity through a renewal receipt notice. You can review the latest guidance on the USCIS green card page or check the status of a pending card through our case status guide.
Tukki is a U.S. immigration provider that helps skilled professionals and their employers with employment-based visas and green cards, from H-1B and O-1A to EB-1A and EB-2 NIW, with dedicated attorney support and full case visibility at every step. If you're moving from a temporary visa toward permanent residence, our team can guide you through what each document proves and when you'll need it.