| A To Z Car Stereo | A To Z Car Stereo | — | (951) 977-4442 | Alarm and generators | Murrieta · Alpine County | — | — |
| Adonis Detail | Adonis Detail | tim@adonisdetail.com | (619) 535-9351 | Windows, patio, painters | Vista · Alpine County | — | — |
| Aguilar Plant Care | Aguilar Plant Care | — | (760) 294-2727 | Tree | San Marcos · Alpine County | — | — |
| Air Alpine Repair Experts | Air Alpine Repair Experts | min-ah@airalpinerepairexperts.info | (619) 839-0592 | GC, remodel, ADU | Alpine · Alpine County | — | — |
| Al & Ed's Autosound | Al & Ed's Autosound | — | (760) 758-9494 | Alarm and generators | Vista · Alpine County | — | — |
| Al & Ed's Autosound La Mesa | Al & Ed's Autosound La Mesa | — | (619) 343-3501 | Alarm and generators | La Mesa · Alpine County | — | — |
| Al's Quality Painting Inc. | Al's Quality Painting Inc. | alsqualitypainting1@gmail.com | (760) 806-1398 | Windows, patio, painters | Vista · Alpine County | — | — |
| All AC & Heating | All AC & Heating | — | (619) 467-1125 | HVAC | Alpine · Alpine County | — | — |
| Allegiance Home Inspections | Allegiance Home Inspections | — | (629) 888-7090 | Inspectors | Murrieta · Alpine County | — | — |
| Allied Home Inspection Services INC Ste# E234 | Allied Home Inspection Services INC Ste# E234 | — | (951) 566-7559 | Inspectors | Temecula · Alpine County | — | — |
| Allied Restoration | Allied Restoration | — | (909) 860-1000 | Restoration | Laguna Niguel · Alpine County | — | — |
| Alpha Pest Control Solution | Alpha Pest Control Solution | — | (619) 914-2216 | Pest, tile roofs | Alpine · Alpine County | — | — |
| Alpine AC Repair Pros | Alpine AC Repair Pros | oscar@alpineacrepairpros.info | (619) 353-9517 | GC, remodel, ADU | Alpine · Alpine County | — | — |
| Alpine Air Conditioning & Heating | Alpine Air Conditioning & Heating | — | (951) 443-0766 | HVAC | Moreno Valley · Alpine County | — | — |
| Alpine Air Products | Alpine Air Products | — | (888) 675-2616 | HVAC | Tustin · Alpine County | — | — |
| Alpine Aquatic | Alpine Aquatic | aapoolserviceandrepair@yahoo.com | (619) 507-2849 | Pool | Alpine · Alpine County | — | — |
| Alpine Arborist | Alpine Arborist | — | (619) 790-8733 | Tree | El Cajon · Alpine County | — | — |
| Alpine Contracting | Alpine Contracting | — | (714) 299-7633 | GC, remodel, ADU | Fullerton · Alpine County | — | — |
| Alpine Crest Air Conditioning | Alpine Crest Air Conditioning | — | (209) 286-0801 | HVAC | Irvine · Alpine County | — | — |
| Alpine Door & Trim | Alpine Door & Trim | — | (310) 212-6152 | Windows, patio, painters | Gardena · Alpine County | — | — |
| Alpine Fire Protection District | Alpine Fire Protection District | — | (619) 445-2635 | Alarm and generators | Alpine · Alpine County | — | — |
| Alpine Haus Construction | Alpine Haus Construction | — | (650) 899-4999 | GC, remodel, ADU | Campbell · Alpine County | — | — |
| Alpine Heating & Air Conditioning | Alpine Heating & Air Conditioning | — | (877) 659-0184 | HVAC | Alpine · Alpine County | — | — |
| Alpine Landscape Materials | Alpine Landscape Materials | — | (619) 445-0213 | GC, remodel, ADU | Alpine · Alpine County | — | — |
| Alpine Painting | Alpine Painting | info@alpinepainting.com | (866) 596-0349 | Windows, patio, painters | Alpine · Alpine County | — | — |
| Alpine Plumbing Heating And Air | Alpine Plumbing Heating And Air | — | (626) 608-1032 | HVAC | San Dimas · Alpine County | — | — |
| Alpine Roofing Guys | Alpine Roofing Guys | info@alpineroofingguys.com | (818) 446-3957 | Other roofers | Porter Ranch · Alpine County | — | — |
| Alpine Sierra Plumbing LLC | Nicholas Lee Tripp | — | (530) 208 7210 | Other | Markleeville · Alpine County | — | — |
| Alpine Windowerks | Alpine Windowerks | — | (619) 337-6999 | Windows, patio, painters | Spring Valley · Alpine County | — | — |
| Altantixor AltantixorroofingProtected | Altantixor Altantixorroofing | — | (315) 871-9465 | Tile roofers | La Jolla · Alpine County | — | — |
| Altivion AltivionroofingProtected | Altivion Altivionroofing | — | (447) 291-0803 | Tile roofers | Wildomar · Alpine County | — | — |
| Alto Pest Control | Alto Pest Control | service@altopestcontrol.com | (858) 430-8355 | Pest, tile roofs | Lakeside · Alpine County | — | — |
| Aros Communications | Aros Communications | — | (530) 318 0191 | Electricians | Markleeville · Alpine County | — | — |
| Arvantixor ArvantixorroofingProtected | Arvantixor Arvantixorroofing | — | (762) 429-5800 | Tile roofers | Poway · Alpine County | — | — |
| Audiosport | Audiosport | contact@audiosport1.com | (760) 743-2333 | Alarm and generators | Escondido · Alpine County | — | — |
| Blue Lake Home Theater INC | Thomas Michael Stradtner | — | (530) 544 4663 | Other | Markleeville · Alpine County | — | — |
| Broadhurst Construction | James Joseph Broadhurst | — | (530) 694 2278 | GC, remodel, ADU | Markleeville · Alpine County | — | — |
| Cannon Inspection Services - Home & Commercial Inspections In Temecula Murrieta Menifee & Winchester | Cannon Inspection Services - Home & Commercial Inspections In Temecula Murrieta Menifee & Winchester | tony@homeinspection.today | (619) 823-4133 | Inspectors | Murrieta · Alpine County | — | — |
| Chamberlain Property Management | Chamberlain Property Management | — | (760) 434-7373 | Property managers | Carlsbad · Alpine County | — | — |
| Chavez Built | Chavez Built | — | (530) 721 1075 | GC, remodel, ADU | Markleeville · Alpine County | — | — |