| Chicago, IL | -LIEU PLLC | 35728 | A/E | — |
| Chicago, IL | 2IM Group, LLC | 30534 | A/E | — |
| St Louis, MO | 303rd Engineering Group, LLC | 30199 | A/E | — |
| Lagrange, IL | 845 Design Group, P.C. | 33352 | A/E | — |
| Chicago, IL | A. Epstein and Sons International, Inc. | 20003 | A/E | — |
| Chicago, IL | AAA Engineering, Ltd. | 32259 | A/E | — |
| St Louis, MO | ABNA of Illinois, Inc. | 35414 | A/E | — |
| Burr Ridge, IL | ABNA of Illinois. Inc. | 35413 | A/E | — |
| Lincolnshire, IL | Accurate Group, Inc. | 29474 | A/E | — |
| Kansas City, MO | AECOM Services of Illinois, Inc | 34681 | A/E | — |
| Chicago, IL | AECOM Services of Illinois, Inc. | 30468 | A/E | — |
| Chicago, IL | AECOM Technical Services, Inc. | 31100 | A/E | — |
| Chicago, IL | AltusWorks, Inc. | 29433 | A/E | — |
| Oak Brook, IL | Ameresco, Inc | 40157 | A/E | — |
| Framingham, MA | Ameresco, Inc. | 34751 | A/E | — |
| Indianapolis, IN | American Structurepoint, Inc. | 33687 | A/E | — |
| Chicago, IL | American Surveying & Engineering, Ltd. | 30023 | A/E | — |
| Lombard, IL | American Veteran Engineering, PLLC | 40000 | A/E | — |
| Oak Brook, IL | Anderson, Mikos Architects, Ltd. | 3735 | A/E | — |
| Pontiac, IL | Andrews Engineering ,Inc. | 30142 | A/E | — |
| Lombard, IL | Andrews Engineering, Inc. | 30143 | A/E | — |
| Springfield, IL | Andrews Engineering, Inc. | 30141 | A/E | — |
| Warrenton, MO | Andrews Engineering, Inc. | 30145 | A/E | — |
| Indianapolis, IN | Andrews Engineering, Inc. | 30144 | A/E | — |
| Rockford, IL | Angus-Young Associates, Inc. | 41044 | A/E | — |
| Chicago, IL | APMonarch PLLC | 34945 | A/E | — |
| Schaumburg, IL | Applied Geoscience, Inc. | 23538 | A/E | — |
| Arlington Heights, IL | Aqua Vitae Engineering, LLC | 35547 | A/E | — |
| Herrin, IL | Architechniques, Ltd. | 21841 | A/E | — |
| Chicago, IL | Architrave, Ltd. | 18146 | A/E | — |
| Lombard, IL | ARCON Associates Incorporated | 13633 | A/E | — |
| St Louis, MO | Arcturis, Inc. | 27629 | A/E | — |
| Chapin, IL | Artisan Consulting Engineers, LLC | 33733 | A/E | — |
| Carbondale, IL | Asaturian, Eaton and Associates, Inc. | 1238 | A/E | — |
| Fairview Heights, IL | ASDG, LLC | 29522 | A/E | — |
| Chicago, IL | Atul Karkhanis Architects, Ltd. | 20352 | A/E | — |
| Peoria, IL | Austin Engineering Co Inc | 6800 | A/E | — |
| Baltimore, MD | Ayers/Saint/Gross Incorporated | 34249 | A/E | — |
| Tempe, AZ | Ayers/Saint/Gross, Incorporated | 34577 | A/E | — |
| Washington, DC | Ayers/Saint/Gross, Incorporated | 34576 | A/E | — |
| Chicago, IL | B + A Engineers, Ltd. DBA CCJM Engineers, Ltd. | 11856 | A/E | — |
| Champaign, IL | Bailey Edward Design, Inc. | 29506 | A/E | — |
| Chicago, IL | Bailey Edward Design, Inc. | 29507 | A/E | — |
| Fox River Grove, IL | Bailey Edward Design, Inc. | 32332 | A/E | — |
| Chicago, IL | Baker Barrios Architects, Inc. | 40429 | A/E | — |
| St Charles, IL | Batir Architecture, Ltd. | 30897 | A/E | — |
| Chicago, IL | Bauer Latoza Studio Ltd. | 20512 | A/E | — |
| Chicago, IL | Bauhs Dring Main Ltd. | 28132 | A/E | — |
| Chicago, IL | Baumann Consulting, Inc. | 34260 | A/E | — |
| O'fallon, IL | Baysinger Architects, LLC | 40203 | A/E | — |
| Marion, IL | Baysinger Architects, PLLC | 31398 | A/E | — |
| Macomb, IL | Benton & Associates, Inc. | 29600 | A/E | — |
| Jacksonville, IL | Benton & Associates, Inc. | 4274 | A/E | — |
| Springfield, IL | Berners-Schober Associates Inc | 29455 | A/E | — |
| Green Bay, WI | Berners-Schober Associates, Inc. | 35662 | A/E | — |
| Urbana, IL | Berns, Clancy and Associates, Professional Corporation | 15468 | A/E | — |
| Danville, IL | Berns, Clancy and Associates, Professional Corporation | 25944 | A/E | — |
| Chicago, IL | BHA PLLC | 40564 | A/E | — |
| Marion, IL | BHDG Architects, Inc. | 29471 | A/E | — |
| Edwardsville, IL | BJS Engineering PLLC | 35840 | A/E | — |
| Chicago, IL | bKL Architecture LLC | 32118 | A/E | — |
| Mt Zion, IL | Blank, Wesselink, Cook & Associates, Inc. | 15170 | A/E | — |
| Chicago, IL | Bloom Companies, LLC | 30497 | A/E | — |
| Chicago, IL | Boarman Kroos Vogel Group, Inc. | 30606 | A/E | — |
| Minneapolis, MN | Boarman Kroos Vogel Group, Inc. | 30605 | A/E | — |
| St Louis, MO | Bond Architects, Inc. | 21633 | A/E | — |
| Chicago, IL | Booth Hansen, Ltd. | 29422 | A/E | — |
| Lisle, IL | Bowman Consulting Group, Ltd | 35164 | A/E | — |
| Chicago, IL | Bowman Consulting Group, Ltd. | 32274 | A/E | — |
| Lisle, IL | Bravo Company Engineering, Inc. | 34551 | A/E | — |
| Galesburg, IL | Bruner, Cooper & Zuck, Inc. | 27725 | A/E | — |
| Chicago, IL | Brush Architects, LLC | 32079 | A/E | — |
| Creve Coeur, MO | BSA LifeStructures Inc. | 34736 | A/E | — |
| Carmel, IN | BSA LifeStructures, Inc. | 29198 | A/E | — |
| Arlington Heights, IL | Building Technology Consultants, Inc. | 29436 | A/E | — |
| Downers Grove, IL | Burns & McDonnell Engineering Company, Inc. | 21858 | A/E | — |
| Chicago, IL | Callan Consulting Engineers, Inc. | 41055 | A/E | — |
| Chicago, IL | Calor Design Group, Ltd. | 20981 | A/E | — |
| Chicago, IL | Canopy / architecture + design, LLC | 35137 | A/E | — |
| Manteno, IL | Carlile Architects LLC | 32074 | A/E | — |
| Chicago, IL | Carnow, Conibear & Assoc., Ltd. | 17091 | A/E | — |
| Maplewood, MO | CASCO Diversified Corporation | 35344 | A/E | — |
| Downers Grove, IL | Cedar Street Architecture at TKDA, Inc. | 35722 | A/E | — |
| Springfield, IL | Charles Joseph Pell Architects Incorporated | 21616 | A/E | — |
| Chicago, IL | Chicago Design Network, Inc. | 40338 | A/E | — |
| Rosemont, IL | Christopher B. Burke Engineering, Ltd. | 19446 | A/E | — |
| Effingham, IL | Civil Design, Inc. | 33686 | A/E | — |
| Collinsville, IL | Civil Design, Inc. | 40126 | A/E | — |
| St Louis, MO | Civil Design, Inc. | 30046 | A/E | — |
| Lincoln, NE | Clark & Enersen, Inc. | 35450 | A/E | — |
| Champaign, IL | Clark Dietz, Inc. | 16848 | A/E | — |
| Chicago, IL | Clark Dietz, Inc. | 19057 | A/E | — |
| Oakbrook Terrace, IL | Clark Dietz, Inc. | 34673 | A/E | — |
| St Louis, MO | Code Consultants, Inc. | 23032 | A/E | — |
| Holmdel, NJ | Colliers Engineering & Design, Inc. | 40283 | A/E | — |
| Chicago, IL | Collins Engineers, Incorporated | 13355 | A/E | — |
| New York, NY | COOKFOX Architects LLC | 35136 | A/E | — |
| Denver, CO | Coover-Clark & Associates, Inc. | 30839 | A/E | — |
| Chicago, IL | Cordogan Clark & Associates, Inc. | 28572 | A/E | — |
| Aurora, IL | Cordogan, Clark & Assoc., Inc. | 28573 | A/E | — |
| Sullivan, IL | Courtice/Grayson, LLC | 30547 | A/E | — |
| Aurora, IL | Crawford, Murphy & Tilly, Inc. | 14230 | A/E | — |
| Edwardsville, IL | Crawford, Murphy & Tilly, Inc. | 29194 | A/E | — |
| Springfield, IL | Crawford, Murphy & Tilly, Inc. | 1579 | A/E | — |
| St Louis, MO | Crawford, Murphy & Tilly, Inc. | 3232 | A/E | — |
| Springfield, MO | Crawford, Murphy & Tilly, Inc. | 28472 | A/E | — |
| Indianapolis, IN | Crawford, Murphy & Tilly, Inc. | 29196 | A/E | — |
| Chicago, IL | CSA Partners Ltd. | 34103 | A/E | — |
| Independence, MO | Custom Engineering, Inc. | 33255 | A/E | — |
| St Louis, MO | Custom Engineering, Inc. | 34559 | A/E | — |
| Herrin, IL | D. A. R. T. Design Incorporated | 29580 | A/E | — |
| Chicago, IL | DAAM, LLC | 34941 | A/E | — |
| Chicago, IL | David Mason & Associates of Illinois, Ltd. | 29555 | A/E | — |
| Park Ridge, IL | DBH & Associates Architects Inc. | 31779 | A/E | — |
| Chicago, IL | Delta Engineering Group, LLC | 31186 | A/E | — |
| Chicago, IL | Demonica Kemper Architects, LLC | 31416 | A/E | — |
| Peoria, IL | Demonica Kemper Architects, LLC | 34234 | A/E | — |
| Baltimore, MD | Design Collective, Inc | 35642 | A/E | — |
| Chicago, IL | Design Collective, Inc. | 35643 | A/E | — |
| Chicago, IL | Design Group JEDI Incorporated | 40260 | A/E | — |
| Normal, IL | Design Mavens Architecture PLLC | 35486 | A/E | — |
| Chicago, IL | DesignTeq Consulting Engineers, LLC | 40944 | A/E | — |
| Elmhurst, IL | Dewberry Architects Inc. | 31736 | A/E | — |
| Peoria, IL | Dewberry Architects Inc. | 31650 | A/E | — |
| Peoria, IL | Dewberry Engineers Inc. | 34127 | A/E | — |
| Arlington Heights, IL | Dickerson Engineering, Inc. | 3484 | A/E | — |
| Crystal Lake, IL | Direct Design, Ltd. | 19795 | A/E | — |
| Itasca, IL | DLA Architects, Ltd. | 18136 | A/E | — |
| Chicago, IL | DLR Group Inc. | 26736 | A/E | — |
| Chicago, IL | DLZ Illinois, Inc. | 28730 | A/E | — |
| Joliet, IL | DLZ Industrial Surveying, Inc. | 31505 | A/E | — |
| Anna, IL | Dodd Architects PLLC | 40023 | A/E | — |
| Akron, OH | Domokur & Associates, LLC | 32193 | A/E | — |
| Chicago, IL | Doyle & Associates Architects and Interior Designers | 21303 | A/E | — |
| Chicago, IL | Drucker Warner Associates, Inc | 30478 | A/E | — |
| O'fallon, IL | Ducks Unlimited, Inc. | 40873 | A/E | — |
| Memphis, TN | Ducks Unlimited, Inc. | 40872 | A/E | — |
| Chicago, IL | Eckenhoff Saunders Architects, Inc. | 26437 | A/E | — |
| Buffalo Grove, IL | ECS Midwest, LLC | 31827 | A/E | — |
| Collinsville, IL | EDM Incorporated | 27800 | A/E | — |
| Herrin, IL | Eggemeyer Associates Architects Inc. | 26859 | A/E | — |
| Hillside, IL | Elara Energy Services, Inc. | 30135 | A/E | — |
| Evanston, IL | Enercon, Ltd. | 5183 | A/E | — |
| Warrenville, IL | Engineering Resource Associates, Inc. | 19605 | A/E | — |
| Chicago, IL | Environmental Design International, Inc. | 21668 | A/E | — |
| Arlington Heights, IL | Erika L. Bolger DBA SEMA Engineering Consultants, LLC | 41046 | A/E | — |
| Urbana, IL | ESCA Consultants, Inc. | 2413 | A/E | — |
| Chicago, IL | EVA Design and Engineering, LLC | 35360 | A/E | — |
| Springfield, IL | Evan Lloyd Associates, Inc. | 16668 | A/E | — |
| Chicago, IL | Exp U.S. Services Inc. | 32109 | A/E | — |
| St Louis, MO | Faith Group, L.L.C. | 33845 | A/E | — |
| Champaign, IL | Farnsworth Group, Inc. | 29142 | A/E | — |
| Pontiac, IL | Farnsworth Group, Inc. | 28416 | A/E | — |
| Normal, IL | Farnsworth Group, Inc. | 30058 | A/E | — |
| Peoria, IL | Farnsworth Group, Inc. | 28417 | A/E | — |
| Springfield, IL | Farnsworth Group, Inc. | 34869 | A/E | — |
| St Louis, MO | Farnsworth Group, Inc. | 28420 | A/E | — |
| Indianapolis, IN | Farnsworth Group, Inc. | 30589 | A/E | — |
| Waukee, IA | Farnsworth Group, Inc. | 30590 | A/E | — |
| Chicago, IL | Farr Associates Architecture and Urban Design, P.C. | 27745 | A/E | — |
| Sioux City, IA | FEH Associates, Inc. | 31125 | A/E | — |
| Champaign, IL | Fehr-Graham & Associates LLC | 32238 | A/E | — |
| Aurora, IL | Fehr-Graham & Associates LLC | 40301 | A/E | — |
| Rochelle, IL | Fehr-Graham & Associates LLC | 29822 | A/E | — |
| Springfield, IL | Fehr-Graham & Associates LLC | 30091 | A/E | — |
| Freeport, IL | Fehr-Graham & Associates LLC | 29253 | A/E | — |
| Marion, IL | Fehr-Graham & Associates LLC | 40302 | A/E | — |
| Rockford, IL | Fehr-Graham & Associates LLC | 29254 | A/E | — |
| Monroe, WI | Fehr-Graham & Associates LLC | 29255 | A/E | — |
| Springfield, IL | Fendrich Engineering, Inc. | 22463 | A/E | — |
| Chicago, IL | FGM Architects Inc. | 30880 | A/E | — |
| Westchester, IL | FGM Architects Inc. | 30358 | A/E | — |
| O'fallon, IL | FGM Architects Inc. | 30360 | A/E | — |
| Indianapolis, IN | Fink Roberts & Petrie, Inc. | 30040 | A/E | — |
| Chicago, IL | Fitzgerald Architecture Planning Design, Inc. | 35095 | A/E | — |
| Madison, WI | Flad & Associates, Inc. | 27603 | A/E | — |
| Oak Park, IL | Forma Architecture, Ltd | 29993 | A/E | — |
| Highland, IL | Formation Architects Inc. | 29581 | A/E | — |
| Chicago, IL | Fresh Coast Capital LLC dba Greenprint Partners | 40025 | A/E | — |
| Savoy, IL | Fuhrmann Engineering, Inc. | 34412 | A/E | — |
| Collinsville, IL | Fuhrmann Engineering, Inc. | 34411 | A/E | — |
| Peoria, IL | Fuhrmann Engineering, Inc. | 34409 | A/E | — |
| Springfield, IL | Fuhrmann Engineering, Inc. | 28140 | A/E | — |
| Chicago, IL | Future Firm PLLC | 34825 | A/E | — |
| Champaign, IL | G.H.R. Engineers & Associates, Inc. | 26673 | A/E | — |
| Chicago, IL | Gannett Fleming Architects, Inc. | 29054 | A/E | — |
| Peoria Heights, IL | Gannett Fleming Architects, Inc. | 40714 | A/E | — |
| Rockford, IL | Gary W. Anderson & Associates, Inc. | 18211 | A/E | — |
| Chicago, IL | Garza Karhoff Engineering, LLC | 30895 | A/E | — |
| Downers Grove, IL | Gasperec Elberts Consulting, LLC | 34396 | A/E | — |
| Chicago, IL | GEI Consultants, Inc. | 34574 | A/E | — |
| Woburn, MA | GEI Consultants, Inc. | 34571 | A/E | — |
| Arlington Heights, IL | Geo Services, Inc. | 30668 | A/E | — |
| Northbrook, IL | Geo. Bancroft Engineering, LLC | 31641 | A/E | — |
| Chicago, IL | GFT Infrastructure, Inc. | 18889 | A/E | — |
| Chicago, IL | Ghafari Associates, L.L.C. | 29578 | A/E | — |
| Chicago, IL | Globetrotters Engineering Corporation | 5041 | A/E | — |
| Chicago, IL | Goettsch Partners, Inc. | 29893 | A/E | — |
| Chicago, IL | Golden Star, Incorporated | 26071 | A/E | — |
| Boston, MA | Goody, Clancy & Associates, Inc. | 29213 | A/E | — |
| Chicago, IL | Graef - USA Inc. | 30717 | A/E | — |
| Chicago, IL | Graef - USA Inc. | 30718 | A/E | — |
| Milwaukee, WI | Graef - USA Inc. | 30716 | A/E | — |
| Springfield, IL | Graham and Hyde Architects, Inc. | 25902 | A/E | — |
| St Louis, MO | Gray Design Group of Illinois, Inc. | 30806 | A/E | — |
| Springfield, IL | GreenAssociates Inc | 29328 | A/E | — |
| Itasca, IL | GreenAssociates, Inc. | 29327 | A/E | — |
| Springfield, IL | Greene & Bradford, Inc. of Springfield | 17951 | A/E | — |
| Chicago, IL | Gregory Ramon Design Studio, Inc. | 34796 | A/E | — |
| Chicago, IL | Griskelis Young Harrell, Ltd. | 28684 | A/E | — |
| Schaumburg, IL | GSG Consultants, Inc. | 29894 | A/E | — |
| Elgin, IL | Hampton, Lenzini and Renwick, Inc. | 40998 | A/E | — |
| Norfolk, VA | Hanbury Evans Wright Vlattas + Company | 28187 | A/E | — |
| Mchenry, IL | Hanson Profesional Services, Inc. | 40340 | A/E | — |
| Lisle, IL | Hanson Professional Services Inc. | 29583 | A/E | — |
| Murphysboro, IL | Hanson Professional Services Inc. | 30587 | A/E | — |
| Peoria, IL | Hanson Professional Services Inc. | 28484 | A/E | — |
| Springfield, IL | Hanson Professional Services Inc. | 28483 | A/E | — |
| Rockford, IL | Hanson Professional Services Inc. | 28485 | A/E | — |
| Chicago, IL | Harley Ellis Devereaux Corporation | 29865 | A/E | — |
| Ogden, IL | Hartke Engineering and Surveying, Inc. | 35827 | A/E | — |
| Paxton, IL | Hartke Engineering and Surveying, Inc. | 40914 | A/E | — |
| New York, NY | Hatfield Group Engineering & Architecture, D.P.C. | 35141 | A/E | — |
| Chicago, IL | HDR Architecture, Inc. | 32808 | A/E | — |
| Naperville, IL | Healy, Bender, Patton, & Been, Inc. | 29365 | A/E | — |
| Chicago, IL | Helen Torres & Associates, PLLC | 35154 | A/E | — |
| Chicago, IL | Hellmuth Obata & Kassabaum Inc | 29848 | A/E | — |
| Jerseyville, IL | Heneghan and Associates, P.C. | 16619 | A/E | — |
| Mt Vernon, IL | Heneghan and Associates, P.C. | 26744 | A/E | — |
| Columbia, IL | Heneghan and Associates, P.C. | 29828 | A/E | — |
| Champaign, IL | Henneman Engineering Inc. | 29611 | A/E | — |
| Breese, IL | Henry, Meisenheimer & Gende, Incorporated | 1684 | A/E | — |
| Bloomington, IL | Hewn Studio PLLC | 40525 | A/E | — |
| Volo, IL | Hey and Associates Inc. | 30807 | A/E | — |
| Chicago, IL | HNTB Corporation | 21157 | A/E | — |
| Chicago, IL | Holabird & Root, LLC | 29318 | A/E | — |
| Carbondale, IL | Holcomb Foundation Engineering Company | 5512 | A/E | — |
| Marion, IL | Horner & Shifrin, Inc, | 29883 | A/E | — |
| Chicago, IL | Horner & Shifrin, Inc. | 34008 | A/E | — |
| St Louis, MO | Horner & Shifrin, Inc. | 6656 | A/E | — |
| Mchenry, IL | HR Green, Inc. | 30850 | A/E | — |
| Cedar Rapids, IA | HR Green, Inc. | 29537 | A/E | — |
| Oak Brook, IL | Huff & Huff, Inc. | 3494 | A/E | — |
| Glen Carbon, IL | Hurford Architects, Inc. | 26235 | A/E | — |
| Hillsboro, IL | Hurst-Rosche, Inc. | 1698 | A/E | — |
| East St Louis, IL | Hurst-Rosche, Inc. | 21754 | A/E | — |
| Marion, IL | Hurst-Rosche, Inc. | 25661 | A/E | — |
| Barrington, IL | Hutchinson Design Group, Ltd. | 29100 | A/E | — |
| Willowbrook, IL | Hygieneering, Inc. | 19955 | A/E | — |
| Peoria, IL | IDG Architects + Partners Inc. | 34492 | A/E | — |
| Houston, TX | IDG Architects + Partners Inc. | 41171 | A/E | — |
| Chicago, IL | IMEG Consultants Corp. | 34177 | A/E | — |
| Naperville, IL | IMEG Consultants Corp. | 34176 | A/E | — |
| Gurnee, IL | IMEG Consultants Corp. | 34312 | A/E | — |
| Ottawa, IL | IMEG Consultants Corp. | 34315 | A/E | — |
| Macomb, IL | IMEG Consultants Corp. | 34313 | A/E | — |
| Rock Island, IL | IMEG Consultants Corp. | 34175 | A/E | — |
| Rock Island, IL | IMEG Consultants Corp. | 34310 | A/E | — |
| Peoria, IL | IMEG Consultants Corp. | 35187 | A/E | — |
| Rockford, IL | IMEG Consultants Corp. | 34311 | A/E | — |
| St Louis, MO | IMEG Consultants Corp. | 34178 | A/E | — |
| Indianapolis, IN | IMEG Consultants Corp. | 34179 | A/E | — |
| Bettendorf, IA | IMEG Consultants Corp. | 34314 | A/E | — |
| Chicago, IL | Infrastructure Engineering, Inc. | 26816 | A/E | — |
| Rolling Meadows, IL | Innleadair LLC | 34781 | A/E | — |
| Chicago, IL | Interactive Design, Inc. | 23389 | A/E | — |
| Chicago, IL | Interface Engineering, Inc. | 34078 | A/E | — |
| Portland, OR | Interface Engineering, Inc. | 34072 | A/E | — |
| Chicago, IL | Introba Inc. | 5501 | A/E | — |
| St Louis, MO | Introba Inc. | 40112 | A/E | — |
| Urbana, IL | Isaksen Glerum Wachter, LLC | 29547 | A/E | — |
| Murphysboro, IL | J.T. Blankinship, Inc. | 30810 | A/E | — |
| South Holland, IL | Jacobs and Maciejewski A.I.A. and Associates, Architects, PC | 29403 | A/E | — |
| Fort Worth, TX | Jacobs Consultants, Inc. | 31197 | A/E | — |
| Chicago, IL | Jacobs Engineering Group Inc. | 30627 | A/E | — |
| St Louis, MO | Jacobs Engineering Group Inc. | 31073 | A/E | — |
| Dallas, TX | Jacobs Engineering Group Inc. | 30626 | A/E | — |
| Chicago, IL | Jahn Architecture, Inc. | 15879 | A/E | — |
| Chicago, IL | John Jay Fox III dba Fox & Fox Architects, LLC | 1629 | A/E | — |
| Springfield, IL | John Shafer & Associates, Inc. | 27519 | A/E | — |
| Chicago, IL | Johnson Lasky Kindelin Architects, Inc. | 22186 | A/E | — |
| Wheaton, IL | Johnson Wilbur Adams, Inc. | 30137 | A/E | — |
| Oak Lawn, IL | JP Architects, Ltd. | 34765 | A/E | — |
| Indianapolis, IN | JQOL, Inc. | 40934 | A/E | — |
| Lisle, IL | Juneau Associates, Inc., P.C. | 34670 | A/E | — |
| Granite City, IL | Juneau Associates, Inc., P.C. | 16055 | A/E | — |
| Edwardsville, IL | Juneau Associates, Inc., P.C. | 26105 | A/E | — |
| Chicago, IL | Kahler Slater, Inc. | 35329 | A/E | — |
| Milwaukee, WI | Kahler Slater, Inc. | 23152 | A/E | — |
| Belleville, IL | Kaskaskia Engineering Group, LLC | 29934 | A/E | — |
| Mulkeytown, IL | Kelly Architecture & Consulting, LLC | 40494 | A/E | — |
| Peoria, IL | Kenyon & Associates Architects, Inc. | 27785 | A/E | — |
| Philadelphia, PA | KieranTimberlake, LLC | 35084 | A/E | — |
| Warrenville, IL | Kimley-Horn and Associates, Inc. | 28729 | A/E | — |
| Raleigh, NC | Kimley-Horn and Associates, Inc. | 28186 | A/E | — |
| Chicago, IL | Klein and Hoffman, Inc. | 16080 | A/E | — |
| Quincy, IL | Klingner & Associates, P.C. | 3939 | A/E | — |
| Chicago, IL | KOO LLC | 33884 | A/E | — |
| Chicago, IL | KPFF, Inc. | 31287 | A/E | — |
| St Louis, MO | KPFF, Inc. | 30322 | A/E | — |