ADU Contractors in Oceanside, CA — License-Verified Contractors
Every contractor below holds an active California license with an office of record in Oceanside, verified against CSLB public data as of November 6, 2026: general builders — A (General Engineering) and B (General Building), the classifications that can build an ADU — and the licensed trades ADU construction uses, C-10 Electrical, C-36 Plumbing and C-5 Framing & Rough Carpentry. Listings are alphabetical; the featured builder is labeled, never ranked.
ADU rules — setbacks, size limits, parking, and fees — are set by the local jurisdiction and change often. Before you hire, read the ADU permit process guide and the Southern California ADU cost guide, and verify any license free at CSLB.
Mars Construction Industries Corp
ADU Cities' own design-build team
CSLB #1138550 · A · B · C-36 · C-20
Building ADUs across Los Angeles, Orange, Riverside, San Bernardino, San Diego & Ventura counties
606 license-verified contractors based in Oceanside — page 5 of 13
Evolution Electrical Services
Evolution Electrical Contractors LLC
C-10Excel Siding Inc
BF And J General Construction Inc
BFalcon Electric
C-10Faris Construction Company
ABC-46C-8Final Phase Construction
BFinal Phase Energy LLC
C-10Fire Mountain Home Improvement Inc
BFix A Leak Plumbing LLC
C-36Flachmeier Construction
BFlood Solutions Inc
BFlow Control Plumbing
C-36Fluid Plumbing
Little Plumber Girl
C-36Foldum Corp
BFord Lowell Tyshawn
C-36Forefront Construction
BFortis Millworks Inc
BC-6Frankowski Electric LLC
C-10Frear Construction
BFreedom Automation Inc
C-10G B Construction
BGallardo Kenneth Jacob
BGarcilaso Construction LLC
BGenesis Grading
AGil And Son Electric
C-10Gleeson Civil Construction
AGlobis Electrical Corporation
BC-10Gns Painting
Gns Contracting Inc
BC-33Goethals Electric
C-10Golan Peter L
BGomez Construction Company LLC
BGomez Signature Painting Inc
BC-33Goolsbee Electric
C-10Grace Civil Engineering
AGranahan Construction
BGreen Choice Energy Inc
C-10C-39Greenfield Fence Inc
BC-13C-17C-29Guadiana Construction Company
BH G Royalty Construction Inc
BH L D Construction
BH N S Services Inc
BC-39H2K Construction
BH2K Construction Inc
BHadden Plumbing LLC
C-36Hadry's Construction
BHahn A Construction
BHamilton Construction Company
BHammon Construction
BHarbor Plumbing And Drains LLC
C-36Data source: CSLB public records as of November 6, 2026 · Verify any license at CSLB