| Westlake Payroll Solvere OPCO, LLC CA | Healthcare & Social Assistance | 0 | — | F |
| Westlake Petrochemicals LA | Construction | 0 | — | A |
| Westlake Pipe & Fittings AZ | Manufacturing | 0 | — | A |
| Westlake Pipe & Fittings GA | Manufacturing | 0 | — | B |
| Westlake Pipe & Fittings MS | Manufacturing | 0 | — | D |
| Westlake Pipe & Fittings PA | Manufacturing | 0 | — | D |
| Westlake Pipe & Fittings TN | Manufacturing | 0 | — | A |
| Westlake Plastics Company PA | Manufacturing | 0 | — | F |
| Westlake Royal Building Product - Krestmark TX | Manufacturing | 0 | — | A |
| Westlake Royal Building Products FL | Manufacturing | 0 | — | B |
| Westlake Royal Building Products NC | Manufacturing | 0 | — | D |
| Westlake Royal Building Products OH | Manufacturing | 0 | — | A |
| Westlake Royal Building Products PA | Manufacturing | 0 | — | C |
| WESTLAKE ROYAL BUILDING PRODUCTS SC | Manufacturing | 0 | — | D |
| Westlake Royal Building Products TN | Manufacturing | 0 | — | D |
| Westlake Royal Building Products TX | Manufacturing | 0 | — | A |
| Westlake Royal Building Products VA | Manufacturing | 0 | — | C |
| Westlake Royal Building Products - Franklin OH | Manufacturing | 0 | — | A |
| Westlake Royal Building Products Kutztown PA PA | Manufacturing | 0 | — | F |
| Westlake Royal Building Products-Henderson-NV NV | Manufacturing | 0 | — | A |
| Westlake Royal Roofing FL | Manufacturing | 0 | — | A |
| WESTLAKE ROYAL ROOFING NV | Manufacturing | 0 | — | A |
| Westlake Royal Roofing LLC CA | Manufacturing | 0 | — | F |
| Westlake Royal Roofing LLC CO | Manufacturing | 0 | — | A |
| Westlake Royal Stone PA | Manufacturing | 0 | — | B |
| Westlake Royal Stone SC | Manufacturing | 0 | — | D |
| Westlake Royal Stone LLC CA | Manufacturing | 0 | — | B |
| Westlake Royal Window Solutions - Crest Vinyl Facility TX | Manufacturing | 0 | — | A |
| Westlake Royal Windows LLC TX | Manufacturing | 0 | — | B |
| Westlake Tool & Die OH | Manufacturing | 0 | — | F |
| Westlake Village - C2 Educational Systems, Inc. CA | — | 0 | — | — |
| Westlake Wellbeing Properties, LLC - Four Seasons Hotel Westlake Village CA | — | 0 | — | — |
| Westlake Wellbeing Properties, LLC dba Four Seasons Hotel Westlake Village CA | — | 0 | — | — |
| Westland Construction, Inc UT | Construction | 0 | — | A |
| Westland Dairy MN | Agriculture & Forestry | 0 | — | A |
| Westland Distributing AZ | Wholesale Trade | 0 | — | A |
| WestLand Engineering & Environmental Services AZ | Professional & Technical Services | 0 | — | F |
| WestLand Engineering & Environmental Services NV | Professional & Technical Services | 0 | — | A |
| WestLand Engineering & Environmental Services OR | Professional & Technical Services | 0 | — | A |
| WestLand Engineering & Environmental Services Inc WA | Professional & Technical Services | 0 | — | A |
| Westland Floral Company Carpinteria, Inc. CA | Agriculture & Forestry | 0 | — | A |
| Westland Manufacturing SD | Manufacturing | 0 | — | D |
| Westland Real Estate Group CA | Real Estate | 0 | — | F |
| Westland Real Estate Group NV | Real Estate | 0 | — | F |
| Westland Real Estate Group TX | Real Estate | 0 | — | F |
| Westland Services DBA Sandstrand Services CA | Administrative & Waste Services | 0 | — | F |
| Westlands Water District CA | Utilities | 0 | — | F |
| Westmaas Electric Company MI | Construction | 0 | — | C |
| Westman Logistics Inc. WA | Transportation & Warehousing | 0 | — | F |
| Westmark Anchorage AK | — | 0 | — | — |