| HLHoch Lumber | Yuma | — | ◇ UNVERIFIED |
| HSHog Slat INC. - Lamar Plant | Lamar | — | ◇ UNVERIFIED |
| HIHolcim (us) INC - Fort Collins Terminal | Fort Collins 3.9 Mi. Nw of | — | ◇ UNVERIFIED |
| HIHolcim-wcr INC - Fort Collins | Fort Collins | — | ◇ UNVERIFIED |
| HEHottinger Excavating & Ready Mix | Akron | — | ◇ UNVERIFIED |
| ISInterior Specialists INC | Aurora | — | ◇ UNVERIFIED |
| ITInternational Technifab Spi | Denver | — | ◇ UNVERIFIED |
| IFIrving F Jensen CO Dba Castle Rock Const | Sioux City | — | ◇ UNVERIFIED |
| JCJames Cape & Sons CO | Racine | — | ◇ UNVERIFIED |
| JCJames Cape & Sons CO (erie Strayer Cbp) | Racine, Wi | — | ◇ UNVERIFIED |
| JDJ.e. Dunn Construction | Boulder | — | ◇ UNVERIFIED |
| JCJerico Concrete INC | Yuma | — | ◇ UNVERIFIED |
| JTJohn Todd | Lakewood | — | ◇ UNVERIFIED |
| JMJordan Marble & Granite, LLC | Loveland | — | ◇ UNVERIFIED |
| JMJp Marble & Granite, LLC | Sheridan | — | ◇ UNVERIFIED |
| KWKiewit Western CO | Loveland Area | — | ◇ UNVERIFIED |
 Kilgore Companies Dba Peak Readymix | Grand Junction | — | ◇ UNVERIFIED |
| KDKilgore Dba Peak Mat - Hagen Port Rmc Ba | Silverthorne | — | ◇ UNVERIFIED |
| KCKing Concrete LLC | Thornton | — | ◇ UNVERIFIED |
| LLafarge | Carbondale | — | ◇ UNVERIFIED |
| LWLafarge West, INC. | Golden 7.1 Mi. Sw of | — | ◇ UNVERIFIED |
| LWLafarge West, INC. | Littleton Area | — | ◇ UNVERIFIED |
| LWLafarge West, INC. | Minturn | — | ◇ UNVERIFIED |
| LWLafarge West, INC. | Denver | — | ◇ UNVERIFIED |
| LCLangston Concrete - Langston Redi Mix | Florence | — | ◇ UNVERIFIED |
| LCLawson Construction CO | Lincoln County | — | ◇ UNVERIFIED |
| LRLeone Ready Mix LLC | Trinidad | — | ◇ UNVERIFIED |
| LMLibrestone Marble & Granite, LLC | Commerce City | — | ◇ UNVERIFIED |
| LPLindsay Precast, INC. | Colorado Springs | — | ◇ UNVERIFIED |
| LLL & L Ready Mix Concrete - Haxtun | Haxtun | — | ◇ UNVERIFIED |
| LLL & L Ready Mix Concrete - Holyoke | Holyoke | — | ◇ UNVERIFIED |
| LCLobato Construction - Mc-8t Plant | Platteville | — | ◇ UNVERIFIED |
| LRLottman Ready Mix - Port Concrete Bp | Hugo | — | ◇ UNVERIFIED |
| LRLoveland Ready Mix Concrete | Loveland | — | ◇ UNVERIFIED |
| LRLoveland Ready Mix Concrete INC | Loveland | — | ◇ UNVERIFIED |
| LSLuxury Stone, INC. | Englewood | — | ◇ UNVERIFIED |
| MGMagallanes Granite and Marble | Denver | — | ◇ UNVERIFIED |
| MWManko Window Systems, INC. | Aurora | — | ◇ UNVERIFIED |
| MLManstone, LLC | Colorado Springs | — | ◇ UNVERIFIED |
| MOMarquardt Outdoors, Llcdba Davis Tent an D Awning | Denver | — | ◇ UNVERIFIED |
| MCMartinez Const & Dev CO / Hanging Lakes/ Portable | Unk | — | ◇ UNVERIFIED |
| MMMartin Marietta Materials, INC. | Severance | — | ◇ UNVERIFIED |
| MMMartin Marietta - Rigden Ready Mix | Fort Collins Area | — | ◇ UNVERIFIED |
| MMMartin Marietta - South Santa Fe | Erie | — | ◇ UNVERIFIED |
| MSMaster Stone, LLC | Sheridan | — | ◇ UNVERIFIED |
| MGMetro Granite & Marble INC | Denver | — | ◇ UNVERIFIED |
| MPMetro Pavers INC Portable | Loveland | — | ◇ UNVERIFIED |
| MLMisb, LLC | Colorado Springs | — | ◇ UNVERIFIED |
| MIM.j. International, LLC | Denver | — | ◇ UNVERIFIED |
| MPMobile Pre Mix-brighton | Brighton, 0.5 Mi Nw of | — | ◇ UNVERIFIED |
