AC21 Portability Explained: H1B and Green Card Rights After 180 Days

AC21 (American Competitiveness in the Twenty-First Century Act) is a 2000 law that provides important job mobility protections for H1B workers and employment-based green card applicants. For Indian workers navigating long H1B and green card timelines, understanding AC21 is critical.

AC21 provides two separate portability protections — one for H1B workers and one for green card applicants. These are related but distinct.

AC21 protection #1: H1B work authorization portability

Under INA Section 214(n), when an H1B holder files a new I-129 petition with a new employer, they may work for the new employer as soon as the petition is filed and a receipt notice is issued — without waiting for USCIS to approve the transfer.

If these conditions are met, you may work for the new employer after the petition is filed and receipted — no approval required. See also: H1B Transfer: When Can You Start Work?

AC21 protection #2: Green card priority date portability

Under INA Section 204(j), if your I-140 has been approved for at least 180 days and your I-485 has been pending or is about to be filed, you can change employers and maintain your priority date (and the approved I-140) for your green card application.

Once these conditions are met, the employer's withdrawal of the I-140 does not affect your ability to continue the green card process.

How AC21 green card portability works in practice

When you file I-485 (now or in the future), you include Supplement J — a form confirming the job offer is in the same or similar occupation as the I-140. Your new employer signs this confirmation.

USCIS then evaluates whether the ported I-140 supports your I-485. The officer looks at:

• Whether the I-140 was approved for 180+ days before the job change
• Whether the new job is same or similar by SOC code comparison
• Whether the bona fide job offer still exists

Documenting your AC21 portability claim

1. 1
   Retain copies of your I-140 approval notice (showing approval date).
2. 2
   Calculate the 180-day mark from the approval date.
3. 3
   Secure a letter from your new employer describing the new position and confirming it aligns with the I-140 job.
4. 4
   Have your attorney prepare a Supplement J and an AC21 portability memo documenting the SOC analysis.
5. 5
   Keep records of continuous employment in the same occupation across employers.

When AC21 does NOT protect you

Frequently asked questions

I changed jobs before my I-140 was 180 days old. Did I lose my priority date?

If your employer withdrew the I-140 before 180 days, you generally lose that priority date and the ability to port that I-140. If the I-140 was NOT withdrawn, you might still be able to port it even if you changed jobs before 180 days — consult your attorney for your specific facts.

AC21 says "same or similar" — how strictly does USCIS apply this?

USCIS has issued policy guidance on this. The test is based on SOC codes. A well-documented comparison showing the two roles share the same core duties, required education, and occupational category typically satisfies the requirement. Occupational level changes (individual contributor to manager in the same field) are generally acceptable.

Does AC21 protect me if I change from a large company to a startup?

The size or nature of the employer does not affect AC21 portability — only the occupational classification of the role matters. A startup in the same field with a qualifying role is fine.