State + agency + NAICS page

General Services Administration NAICS 541990 contractors in Illinois

All Other Professional, Scientific, and Technical Services. Use this deeper state-buyer-industry page to see which visible contractors sit closest to this exact overlap in the public AwardRegistry layer.

Illinois + General Services Administration
Last updated: April 8, 2026

Visible recipients

4

Mapped obligations

$1,562,299,908

Top PSC links

4

Top recipients

Visible recipients tied to General Services Administration, Illinois, and NAICS 541990

Alion Science And Technology Corporation

Chicago, IL

Alion Science And Technology Corporation is a federal category business profile based in Chicago, IL. The current public data layer shows $1,391,195,185 in visible federal obligations across 5 awards or transactions. Department of Defense appears as the strongest visible awarding agency. Top industry concentration is in NAICS 541710 (Research and Development in the Physical, Engineering, and Life Sciences). The profile also shows meaningful product and service activity in PSC AZ12.

$83,417,602

Walsh Federal LLC

Chicago, IL

Walsh Federal LLC is a federal category business profile based in Chicago, IL. The current public data layer shows $406,413,501 in visible federal obligations across 169 awards or transactions. Department of Defense appears as the strongest visible awarding agency. Top industry concentration is in NAICS 236220 (Commercial and Institutional Building Construction). The profile also shows meaningful product and service activity in PSC Y1BZ.

$622,102

Hii Mission Technologies CORP

Willowbrook, IL

Hii Mission Technologies CORP is a federal category business profile based in Willowbrook, IL. The current public data layer shows $380,690,397 in visible federal obligations across 464 awards or transactions. Department of Defense appears as the strongest visible awarding agency. Top industry concentration is in NAICS 541330 (Engineering Services). The profile also shows meaningful product and service activity in PSC AZ12.

$1,449,614,863

Aar Government Services, Inc.

Wood Dale, IL

Aar Government Services, Inc. is a federal category business profile based in Wood Dale, IL. The current public data layer shows $254,953,145 in visible federal obligations across 429 awards or transactions. Department of Defense appears as the strongest visible awarding agency. Top industry concentration is in NAICS 488190 (Other Support Activities for Air Transportation). The profile also shows meaningful product and service activity in PSC J015.

$28,645,341