Cómo obtener un número A

Su número de registro de extranjero, o número A, es un número de identificación para personas que no son ciudadanas estadounidenses.

USCIS and the U.S. government use this unique, personal number to track any immigration forms filed. Every immigrant is given a unique number after filing their first immigration form. A-Numbers do not change and are only for those who are not United States citizens.  

It is important to understand that an A-Number is not the same as:  

  • USCIS case number 
  • Form application Receipt Number 
  • Social Security Number 
  • Individual Taxpayer Identification Number  
  • Employment Authorization Number 

USCIS assigns an A-Number to all immigrants who apply to live in the United States permanently. If you apply for a Permanent Resident Card (green card) or another type of Immigrant Visa, you will receive an Alien Number. You will use your A-Number for any USCIS application in your journey to obtain U.S. citizenship. 

Cómo obtener un número A  

If you are an eligible immigrant who is planning to live and work in the United States, you will need to apply for an A-Number. Here are the steps to get an A-Number:  

  • Determine if you are eligible for an A-Number. If you are not a U.S. citizen and you plan to work, live or study in the United States, you are required to have an Alien Registration Number 
  • In order to get your A-Number, you will need to submit Form I-551, Permanent Resident Card (also known as a "green card"), Form I-765, Application for Employment Authorization, Form I-131, Application for Travel Document, or other applicable USCIS forms 
  • After submitting your application, you will be required to attend a biometrics appointment. During this appointment, USCIS will take your fingerprints, photograph, and signature. 
  • After attending your biometrics appointment, you will need to wait for USCIS to approve your application. The processing time for your application will vary depending on the type of application you submitted 
  • Once your application is approved, USCIS will issue you an A-Number. This number will be included on your green card, work permit or other immigration document you receive.  


As of September 2023, the fee for Form I-551 is $540, Form I-765 is $410, and Form I-131 is $575. However, these fees are subject to change, so it is always best to check with USCIS for the most up-to-date information. 

Your Alien Registration Number is generally valid for the duration of your immigration status in the United States. If you are a lawful permanent resident, your Alien Registration Number will be valid for life. However, if you are a non-permanent resident, such as a temporary worker or student, your Alien Registration Number may be valid only for the duration of your visa or work permit. 

USCIS application form for A number

It is important to keep your A-Number documents safe and secure. You will need to provide your A-Number on many official documents and forms, such as tax forms, so it is important to keep it in a safe place. If you lose your A-Number, you will need to apply for a replacement through USCIS. 


La información que figura en tiene únicamente fines informativos generales. No debe tomarse como asesoramiento profesional ni reemplazar la orientación de un profesional.

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