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 8 of 13
Maggio Pacific Construction LLC
BMagic Solar San Diego LLC
C-10C-46Magnum Plumbing Company Inc
C-36Mar Construction
BMarc Douglas Construction
BMarcon Construction
Marcon One Inc
BC-33D-03D-06D-41Marcon G
BMario Brothers Construction Inc
BC-10Mark's Carpenter Service
BMasternak Construction
BMasters Lee
BMata Electric LLC
C-10Mata Enterprises
C-10C-36Maxflow Plumbing
C-36Maximum Plumbing
C-36Mazza Construction
BMc Contracting
BMc Ewan Enterprises
AMc Garvey Paul A
BMc Master Electric Company
Mc Master Electrical Corporation
C-10Mccann Jordan
BMcd Builders
BMcfall Dan Electrical Contractor Inc
C-10Mclay Contracting
BMeath John Construction And Maintenance
BMerribuild
Paul Merrick Construction Inc
BMighty Fire Breaker LLC
BC-16C-36Miller Chaun
BMiramontes Construction
BMitchell Construction
BMojica Plumbing Inc
C-36Montana Construction
BMontgomery Design Build
BMoore Construction
Responsible Construction Inc
BMoreau Brad Construction
BMorrissey T Corporation
ABC-8HAZMulder Construction
BMulti-plex International
BMusick Construction Inc
BNarcy Construction & Roofing Inc
BC-39Nesti Construction Inc
BNew Legacy Custom Building & Design Inc
BNew Way Plumbing Inc
C-36Nguyen T A Construction Inc
BC-10C-46Nicolet David A Construction
BNishimura Robert Inc
BNl Custom Building
BNlb Plumbing
C-36Noir Development
BData source: CSLB public records as of November 6, 2026 · Verify any license at CSLB