| A and A Plaster and Drywall | Interior Trades | Drywallers | Plaster |
| A and R Hill Roofing | Exterior Trades | Roofers |
| A and R Painting | Interior Trades | Painters |
| A Better Price Contracting | Exterior Trades | Roofers |
| A Cut Above Tree and Landscaping | Site Work | Landscaping | Tree Trimmers |
| A Fast Repair Company | Carpenters | Handymen/women |
| A Woman’s Touch | Handymen/women |
| A-All Lock and Key Company | Services | Locksmith |
| AA Air Conditioning | Building Systems | Heating and Cooling |
| AAA Missouri Tub and Tile | Tub Reglazing |
| ABA Inspections and Consulting | Home Inspectors |
| Abbot Lock and Key | Services | Locksmith |
| ABC Key and Door | Services | Locksmith |
| Able Key and Service | Services | Locksmith |
| Absolute Service Co. | Exterior Trades | Tuckpointers |
| Ace Maintenance | Scaffolding |
| ADT | Supply and Install | Security/Alarm |
| Affordable Tree Service | Site Work | Tree Trimmers |
| Ali, Eric | Interior Trades | Drywallers | Painters |
| Alliance Roofing and Tuckpointing | Exterior Trades | Tuckpointers |
| Aluminum Gutter and Materials | Exterior Trades | Gutters - Install and Repair |
| Always Reasonable Plumbing | Building Systems | Plumbers |
| AMC Tile | Supply and Install | Tile |
| American Craftsman | Exterior Trades | Fireplace and Flue Repair | Gutters - Install and Repair | Copper Gutter Supply |
| American Institute of Architects | Architects and Designers |
| Anderson Drywall | Interior Trades | Drywallers |
| Anderson Windows | Windows |
| Andre Tuckpointing | Exterior Trades | Tuckpointers |
| Apple City | Cabinetry |
| Arbor Tree Service | Site Work | Tree Trimmers |
| Architective Home Inspection Ltd. | Home Inspectors |
| Architectural Accents | Architectural Salvage |
| Architectural Artifacts | Architectural Salvage |
| Architectural Stone | Stone |
| Aries Plumbing | Building Systems | Plumbers |
| Art Glass Creations | Stained Glass |
| Art Glass Unlimited | Stained Glass |
| Artisan Design and Construction | Services | Flooring - Refinish | Paint Removal and Refinish |
| Artisan Marble and Granite | Countertops | Stone |
| Artistic Glassworks | Stained Glass |
| Aulbach, Eric | Interior Trades | Plaster |
| Awtrey Heating and Air Conditioning | Heating and Cooling |
| B and B Handyman | Handymen/women |
| B and C Slate and Tile | Exterior Trades | Roofers |
| B and M Plumbing | Building Systems | Plumbers |
| Badgett Construction | Concrete and Asphalt | Concrete Flatwork |
| Banner Plumbing | Building Systems | Plumbers |
| Bar Association of Metro St. Louis | Attorneys |
| Barr Brothers | Interior Trades | Plaster |
| Bates Electric | Building Systems | Electricians |
