Executive Summary
Foreign-born workers are a critical driver of U.S. innovation. In 2023, they accounted for 23.6 percent of the science, technology, engineering, and math (STEM) workforce. Many of America’s leading technology companies rely on highly skilled temporary workers to fill shortages in specialized positions and maintain their global competitiveness. However, foreign nationals’ access to nonimmigrant work visa categories remains increasingly uncertain due to federal policy shifts and processing inefficiencies. Continued political pressure and growing adjudication delays threaten to exacerbate the system’s existing bottlenecks.
This report analyzes U.S. Citizenship and Immigration Services (USCIS) processing trends for Form I-129 petitions associated with H-1B, L-1A, L-1B, and O visa categories. It uses the quarterly data on initial petitions from USCIS between fiscal year (FY) 2016 and FY2025, compiled in the American Immigration Council’s USCIS Filing Trends Dashboard, to assess how processing trends have evolved over time and across presidential administrations.
The analysis finds growing evidence of processing strain within USCIS for high-skilled nonimmigrant petitions. Demand for beneficiaries of these petitions remained strong throughout the decade, particularly for H-1B workers, as USCIS increasingly failed to keep pace with incoming petitions. Backlogs grew, backlog clearance times lengthened, and efficiency ratios declined in several visa categories. At the same time, shifting policy and enforcement priorities led to substantially varied adjudication outcomes across visa categories and administrations, posing greater challenges for both employers and workers.
Key Findings
High-skilled nonimmigrant visa categories remain a major pathway for employment-based immigration. Between FY2016 and FY2025, nonimmigrant work visa categories accounted for almost three quarters of all approved employment-based petitions for high-skilled workers (Form I-129 for nonimmigrant and Form I-140 for immigrant petitions combined).
Demand for high-skilled nonimmigrant workers keeps rising. Annual H-1B filings increased by 14.5 percent during this period, reaching 456,724 petitions in FY2025. O filings rose by 68.6 percent, from 5,390 to 9,086, in FY2025 Q4, reflecting increased use of this pathway for high-skilled talent.
Backlogs have increased sharply in recent years. Following several years of reductions, pending Form I-129 petitions grew by 175.6 percent between FY2023 Q2 and FY2025 Q4. In FY2025, of all the high-skilled nonimmigrant visa categories, H-1B petitions experienced the fastest growth in backlogs, nearly doubling, from 66,894 to 124,638, an indication that USCIS was not keeping up with a surge in new petitions.
USCIS has increasingly failed to keep pace with demand. Efficiency ratios for several visa categories fell below 1.0 in recent years, indicating the agency completed fewer petitions than it received and added to existing backlogs. Backlog clearance times also increased across multiple categories in FY2025.
Petitions receiving requests for evidence (RFEs) have become increasingly likely to be approved. Between FY2017 Q1 and FY2025 Q4, approval rates for completed petitions with RFEs increased by 9.1 percentage points for H-1B petitions, 4.5 points for L-1A petitions, and 27.4 points for L-1B petitions.
After declining sharply during the first Trump administration, approval rates have recovered. H-1B approval rates fell from 92.2 percent in FY2017 Q1 to 75.4 percent in FY2019 Q1, then rebounded and remained above 95 percent from FY2020 Q3 through FY2025 Q4. L-1A and L-1B petitions followed similar trends; and O petitions remained comparatively stable. Since FY2017, USCIS approved an average of 452,566 high-skilled nonimmigrant visa petitions per year, supporting hundreds of thousands of high-skilled nonimmigrant workers and their employers.
H-1B petitions generally receive the most favorable adjudication outcomes. In the past decade, H-1B petitions experienced the highest average efficiency ratio (1.03) and approval rate (97.8 percent), along with the lowest rates of completion with RFE (8.5 percent).
L-1 petitions face the greatest adjudicative challenges. Although L-1 petitions had the shortest processing time (3 months) compared with H-1B and O petitions, L-1A and, particularly, L-1B petitions experienced higher rates of requests for evidence (RFEs) and lower approval rates.
Processing delays extend beyond the sponsored workers. H-4 spouses seeking work authorization faced average waits of 6.5 months when applications were filed concurrently with their H-4 petitions, but 16.5 months when filed afterward, matching the processing time of EAD applications by L-2 spouses and delaying labor market participation for many high-skilled immigrants.
Overall, the findings show that although the United States continues to attract high-skilled talent, growing backlogs, declining processing efficiency, and fluctuating adjudication standards creates significant uncertainty for employers and workers alike.
