The permanent residency process will vary in length, depending on which preference category is appropriate for your case and where you work (which state). In addition, government processing times are extremely inconsistent and subject to change. Generally there are three stages for employment-based cases.
Stage 1: Labor Certification – The employer must demonstrate to the Department of Labor that it is unable to locate qualified or available U.S. workers for your position. This process can be lengthy depending on processing at the Department of Labor.
Note: Some employees may be eligible to skip the Labor Certification process if they qualify for inclusion in the first preference category or as a person of exceptional ability in the second preference category.
Stage 2: I-140 (Immigrant Visa Petition) – The employer must petition on your behalf to USCIS to classify you in one of the employment-based preference categories for permanent residence. This can take six to nine months or longer depending on USCIS processing times. To view current processing times, please refer to the Government Processing Times link.
Stage 3: I-485 (Adjustment of Status) – This is an application by the employee and his or her dependent family members to change from nonimmigrant status to permanent resident status. This can take anywhere from one to two years or more depending upon which USCIS Service Center has jurisdiction over the application. Alternatively, an application for an immigrant visa can be made at a U.S. consular post outside the U.S. This process is much quicker than adjusting status, but it requires a personal appearance at the consular post for an interview.
Note: It is now possible in certain circumstances to file an application for adjustment of status concurrently with the I-140 petition. In order to use concurrent filing, you must qualify for one of the first three employment-based preference categories and an immigrant visa must be immediately available to you.
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O-1 (Extraordinary Ability) Visa