The HR guide to I-9 permanent resident cards

This year's immigration changes are a lot to track. Getting your I-9s right doesn't have to be.

In May 2026, USCIS issued a policy memo that upended a process green card applicants have relied on for decades: applying for permanent residency from inside the U.S. The change sparked confusion, congressional pushback, and a wave of questions from employers trying to figure out what it means for their workforce.

That uncertainty spills right into Section 2 of Form I-9, where employers verify Permanent Resident Cards every day. Nearly 13 million people currently hold green cards in the U.S., so getting this right is a routine part of hiring for employers across nearly every industry. And the stakes are climbing: ICE's rate of Notices of Inspection in the first half of 2025 ran roughly ten times higher than in 2024.

Here's the good news: this is easier to get right than it sounds. Below, we'll cover exactly where the card number lives, how it's different from an A-Number, and everything else you need for confident I-9 verification.

What is the Permanent Resident Card number?

The I-9 Permanent Resident Card number—also called the Green Card—is a unique identifier assigned to a specific physical green card. On current designs (issued after January 2023), it's a 13-character code: three letters followed by ten numbers.

Here's where it gets confusing: Green Cards also carry an A-Number, or Alien Registration Number. The A-Number identifies the person while the card number identifies the card:

• A-Number: 7 to 9 digits, usually written with an "A" prefix. Permanent—stays with the card holder for life, even through renewals. Found on the front, labeled "USCIS#."
• Card number: Changes with every new card. Renew a Green Card, and the holder gets a new Document Number—their A-Number never moves.

This distinction matters more than ever. As of March 2026, ICE reclassified missing A-Numbers and USCIS numbers in Section 1 as a substantive violation—meaning there's no more 10-day window to fix that error once ICE flags it.

Where do you find the Permanent Resident Card number?

The document number on a permanent resident card sits on the back, in a line of machine-readable text near the bottom. The front holds the photo, name, date of birth, and USCIS number.

However, it’s important to note that not every card in circulation is the current version. USCIS redesigns the Permanent Resident Card every three to five years, and older designs stay valid until their printed expiration date:

• Cards issued since May 2010 still carry the number on the back.
• Pre-2010 cards sometimes show it on the front, occasionally under a different label.
• Cards issued between 1977 and 1989 are peach-colored, have no expiration date, and don't follow the same format at all.

How is the card number used during the I-9 process?

A Permanent Resident Card is a List A document: it proves identity and work authorization on its own.

Verification happens in one of three compliant ways:

• In-person: The traditional route
• Authorized representative: Someone you designate to review on your behalf
• USCIS alternative procedure: Available to e-verify-enrolled employers, allowing remote review through secure upload and live video—something over 1.4 million employers are enrolled in.

If you're verifying remote hires, our guide to remote I-9 verification covers exactly what's required.

Once verified, Section 2 requires:

• The document title
• The issuing authority
• The Document Number
• The expiration date

For the full breakdown of every I-9 section, see our Form I-9 guide.

I-9 permanent resident card number: Common mistakes & best practices

Even careful HR teams get tripped up by green cards. Here are the most frequent issues we see:

• Confusing the card number with the A-Number: It's the single most common green card error on Form I-9—and an easy one to make, since both numbers sit on the same document.
• Recording the wrong identifier in the wrong section: The A-Number belongs in Section 1. The Document Number belongs in Section 2. Swap them, and you've got a substantive error waiting to surface in an audit.
• Requesting unnecessary documentation: A valid Green Card is a complete List A document. Asking for more—even with good intentions—can expose you to discrimination claims.
• Manual data entry errors: A single mistyped character in a 13-character alphanumeric code is enough to make a form inaccurate. 

None of these mistakes are inevitable. A few routine checks and balances go a long way:

• Train your HR team on document recognition: Card designs change every few years. What your team learned five years ago may not match what's showing up in new hire paperwork today.
• Review document information carefully before submission: Slow down at the moment of data entry. A quick double-check catches most errors before they become fines.
• Stay current on Form I-9 requirements: Check USCIS's I-9 Central page quarterly for updates. ICE guidance and card designs both shift without much notice, so a standing calendar reminder beats relying on "what we've always done."
• Use an electronic I-9 and E-Verify solution: Tools like WorkBright's I-9 & E-Verify software with built-in Document Verification reduce manual entry, flag document errors before form submission, and keep an audit trail that shows good-faith compliance.

The number that's worth getting right

One swapped digit or mixed-up identifier can turn a routine I-9 into a substantive violation—and in a year of shifting immigration policy and rising audit activity, there's not much margin for error. Knowing where the card number lives, how it differs from the A-Number, and what belongs in each section of Form I-9 puts you ahead of most audit triggers.

But knowledge alone only goes so far at scale. When United AG & Turf merged ten companies and 500+ employees into one organization in under two weeks, an electronic I-9 platform is what turned that volume of paperwork into an estimated $1 million in avoided risk. 

Systems like WorkBright do just that—for any team, at any scale. It reduces manual entry errors, flags issues before they reach an audit, and keeps your process consistent and compliant, hire after hire.

Learn more about how WorkBright's I-9 & E-Verify software can help you get there.