| Km Landscaping Corp | Thuc Kim Nguyen | — | (925) 588 8789 | Windows, patio, painters | Manteca · San Joaquin County | — | — |
| Kms Door Company LLC | Kurtis Michael Staab | — | (209) 329 8092 | Other | Acampo · San Joaquin County | — | — |
| Knd Electric | Kenneth Nicholas Jr Duarte | — | (925) 580 2830 | Electricians | Tracy · San Joaquin County | — | — |
| Knellson General Contracting | David Eugene Knell | — | (916) 240 7705 | GC, remodel, ADU | Ripon · San Joaquin County | — | — |
| Knights Flooring INC | Joseph Patrick Manson | info@knightsflooringinc.com | (925) 231 1300 | Other | Stockton · San Joaquin County | — | — |
| Knights Plumbing And Drain | Leslie Jean Hammond | — | (209) 823 1717 | Other | Lathrop · San Joaquin County | — | — |
| Know How LLC | Michael Patrick Murray | — | (209) 321 4960 | GC, remodel, ADU | Tracy · San Joaquin County | — | — |
| Korock Construction | Robert Mark Korock | — | (209) 327 3818 | GC, remodel, ADU | Acampo · San Joaquin County | — | — |
| Kostas HVAC INC | Kostiantyn Staryhin | — | (209) 618 6077 | HVAC | Mountain House · San Joaquin County | — | — |
| Krotter Fences | Krotter Fences | — | (209) 405 8877 | Other | Stockton · San Joaquin County | — | — |
| Krueger & Company INC | Christopher Kenneth Krueger | firstname@krueger.com | (925) 876 8226 | GC, remodel, ADU | Ripon · San Joaquin County | — | — |
| Ks Construction And Developers INC | Singh Ajay | — | (209) 216 7198 | GC, remodel, ADU | Mountain House · San Joaquin County | — | — |
| Kudenov Construction & Maintenance Co | Phillip Michael Kudenov | — | (209) 481 3961 | Electricians | Lodi · San Joaquin County | — | — |
| Kudenov Construction Services | Christopher Paul Kudenov | — | (209) 607 0976 | GC, remodel, ADU | Stockton · San Joaquin County | — | — |
| Kulbir Singh Randhawa | Kulbir Singh Randhawa | — | (209) 814 4228 | GC, remodel, ADU | Tracy · San Joaquin County | — | — |
| Kuldeepak Goswamy | Kuldeepak Goswamy | — | (408) 421 8663 | GC, remodel, ADU | Tracy · San Joaquin County | — | — |
| Kulp Drywall INC | Harry Kenneth Jr Kulp | — | (209) 992 0514 | GC, remodel, ADU | Manteca · San Joaquin County | — | — |
| Kyle's Custom Tile Stone Co | Kyle Raymond Ferreira | — | (209) 612 1447 | Other | Woodbridge · San Joaquin County | — | — |
| L & G Remodeling Of Stockton | Luna Gabriel | — | (209) 607 7322 | GC, remodel, ADU | Stockton · San Joaquin County | — | — |
| L & L Construction Co | Ronald Leroy Jr Clayton | — | (209) 275 7539 | GC, remodel, ADU | Manteca · San Joaquin County | — | — |
| L & S Concrete | L & S Concrete | — | (209) 242 1171 | Other | Stockton · San Joaquin County | — | — |
| L & W Cabinets INC | Heidi Louise Schallberger | — | (209) 333 8222 | Other | Stockton · San Joaquin County | — | — |
| L And S Concrete And Design | Larry Leroy Mitchell | — | (209) 333 2948 | Other | Lodi · San Joaquin County | — | — |
| L B Lightswest | Leo Paul Iii Burke | — | (209) 333 0996 | Electricians | Lodi · San Joaquin County | — | — |
| L D B D INC | Larry Allen Duarte | — | (209) 597 2641 | Other | Tracy · San Joaquin County | — | — |
| L E C S | L E C S | — | (209) 639 4391 | Other | Stockton · San Joaquin County | — | — |
| L G Electric | Luis Alfonso Gonzalez | lgelectric@lgelectric.com | (209) 993 1429 | Electricians | Linden · San Joaquin County | — | — |
| L J | L J | — | (209) 456 3960 | Other | Manteca · San Joaquin County | — | — |
| L J Roman's Heating & Air INC | Lawrence James Roman | — | (209) 482 6267 | HVAC | Lathrop · San Joaquin County | — | — |
| L Jevity Flooring | L Jevity Flooring | — | (619) 455 2477 | Other | Stockton · San Joaquin County | — | — |
| L M H Development | L M H Development | — | (209) 649 0202 | GC, remodel, ADU | Stockton · San Joaquin County | — | — |
| L M Plumbing And Drain Cleaning | Luis Jesus Melgar | — | (209) 640 0153 | Other | Manteca · San Joaquin County | — | — |
| L R Varwig & Sons INC | Luallen Roger Jr Varwig | — | (209) 993 6110 | Other | Stockton · San Joaquin County | — | — |
| La Munyon Construction | Steve Lynn La Munyon | — | (209) 815 5828 | GC, remodel, ADU | Escalon · San Joaquin County | — | — |
| La Tierra Verde Landscape INC | Saul Cruz Hernandez | — | (209) 467 3362 | Windows, patio, painters | Stockton · San Joaquin County | — | — |
| Lackey's Electrical Service | John Arnold Lackey | — | (206) 606 7525 | Electricians | Manteca · San Joaquin County | — | — |
| Lainez Electric | Melvin Alexander Lainez Cerrato | alexl@lainezelectric.com | (650) 644 5235 | Electricians | Manteca · San Joaquin County | — | — |
| Lalo's Tile Corp | Del Castillo Nuno Eduardo | — | (510) 712 6635 | Other | Manteca · San Joaquin County | — | — |
| Lamb Heating & Air Conditioning | Lamb Heating & Air Conditioning | — | (209) 663 8085 | HVAC | Lockeford · San Joaquin County | — | — |
| Lams Drywall | Lams Drywall | — | (209) 684 3526 | Other | Stockton · San Joaquin County | — | — |