Building Design+Construction (sister publication to American School & University) has released its 2026 rankings of the nation’s largest K-12 architecture, engineering, and construction firms as part of its annual Giants 400 Report.

The three rankings offer a broad look at the firms doing the most business in the school facilities sector, from architects planning new and modernized campuses to engineering firms tackling building systems and infrastructure and contractors delivering the projects.

BD+C’s Top 160 K-12 School Architecture Firms for 2026 is led by PBK, followed by MOREgroup, DLR Group, VLK, Stantec, Wold Architects and Engineers, Perkins Eastman, Corgan, HMC Architects, and Pfluger Architects. PBK also headed the 2025 list, while MOREgroup moved ahead of VLK and DLR Group among this year’s leaders.

The Top 90 K-12 School Engineering Firms for 2026 places AECOM at the top, followed by CMTA, Jacobs, WSP, Salas O’Brien, IMEG, GFT, NV5 Global, and STV. AECOM also led last year’s engineering ranking, although CMTA and Jacobs switched positions among the top three.

On the construction side, CORE Construction leads the Top 100 K-12 School Construction Firms for 2026, followed by Pogue Construction, Gilbane Building Company, Joeris General Contractors, Bartlett Cocke General Contractors, Balfour Beatty US, and Satterfield & Pontikes Construction. CORE also ranked first in 2025, when Gilbane and Pogue occupied the next two positions.

Part of BD+C’s 50th Giants 400

The K-12 lists are part of the 50th edition of BD+C’s Giants 400 Report. Nearly 600 architecture, engineering, and construction firms submitted data for this year’s report, which includes 137 rankings across 25 building sectors and specialty categories.

BD+C ranks firms based on gross revenue from work performed by their U.S.- and Canada-based operations. For the K-12 sector, the rankings cover public, private, charter, and military schools and separately track architecture and architecture/engineering firms, engineering and engineering/architecture firms, and contractors and construction management firms.

Taken together, the three rankings provide a useful view of the companies with the largest financial footprint in the K-12 building market. They also arrive as school districts continue to navigate widely different facilities conditions—from enrollment growth and demand for added capacity in some regions to aging buildings, modernization needs, and excess space in others.

American School & University will add another perspective on those market conditions with the forthcoming 2026 AS&U 100, its annual ranking of the nation’s largest public school systems by enrollment. This year’s data will provide a closer look at where the country’s largest districts are concentrated and how changing enrollment patterns could influence future facilities planning and capital investment.