San Diego International Airport (SAN) announced it will begin construction on Phase 1B of the New Terminal 1 (New T1) project — the building that will finish the rebuilt Terminal 1 by building the final 11 gates and passenger facilities once Phase 1A opens.
The San Diego County Regional Airport Authority made the announcement on Friday, September 5 2025 that construction in Phase 1B for New T1 will begin with essential closures starting Monday, September 8, 2025
To allow for the construction, the Terminals 1 and 2 arrivals roadway will be closed starting Sept. 8 in preparation for the construction. Drivers traveling between the two terminals will be required to use designated on-airport detours.
The airport authority also published detailed maps, below, and an animated detour video to help motorists adapt to the change.
What Phase 1B will deliver?
Phase 1B completes the New T1 program by building 11 additional gates, extra passenger amenities (including customer lounges) and significant airside and landside infrastructure enhancements. Combined with Phase 1A (19 gate additions), the New T1 will include 30 gates, expanded concessions, a new on-airport road and a major parking plaza.
After September 22 evening, when the final flights have departed, the existing Terminal 1 will close and be demolished. The Phase 1B will be constructed on the site of the existing Terminal 1.
The airport is moving towards preparatory work with Phase 1A in the future for passenger operations (September 2025 arrival of Phase 1A’s initial flights). Construction of Phase 1B will follow the opening of Phase 1A and will include demolition of the footprint of existing Terminal 1 to allow for new concourse and associated airfield work. Airport and project schedules have the intent to open Phase 1B in early 2028, with some of the airside completion activity pushed into mid-2028.
Local impacts and detours
Local residents and passengers can expect ongoing detours and occasional routing changes until Phase 1B is constructed — some of the detours will remain in place until Phase 1B is finished in 2028, the New T1 project team says. The work also included gate shuffles and temporary repositioning of a few carriers during construction. The Authority has been publishing construction-impact guidance and detour maps to help travelers plan ahead.
Funding and approvals
Phase 1B draws financing from a mix of sources and federal grants; SAN disclosed that it received a federal grant for Phase 1B work financing, and the entire New T1 program constitutes an around $3.8 billion redevelopment that has utilized airport financing and other sources. The airport worked with the FAA and agencies locally to coordinate airfield construction sequencing and environmental controls.
Why Phase 1B matters?
Finishing Phase 1B will reclaim and add gate capacity at SAN and complete the modernized Terminal 1 passenger experience — more gates, more concessions and reconfigured roadway access that will mitigate surface congestion and improve passenger flow. Finishing Phase 1B (and the airside work that accompanies it) represents an ultimate, complex step because it requires demolition within the active airport footprint and demands careful planning of airplane movement and taxiways.
San Diego International Airport New Terminal 1 Phase 1B Project Factsheet
Project Overview
San Diego International Airport (SAN) is preparing to begin construction on Phase 1B of the New Terminal 1 (New T1) project, which will complete the rebuilt Terminal 1 by adding the final 11 gates and passenger amenities after Phase 1A enters service.
Key Dates & Timeline
Construction Preparation Begins: September 8, 2025 (arrivals roadway closure)
Existing Terminal 1 Closure: September 22, 2025 (permanent closure and demolition)
Phase 1A Opening: September 2025
Phase 1B Target Completion: Early 2028
Final Airside Work: Mid-2028
Project Scope & Deliverables
Phase 1B Components
11 additional aircraft gates
Enhanced passenger amenities including customer lounges
Major airside and landside infrastructure upgrades
Construction on the site of the existing Terminal 1
Combined New Terminal 1 Capacity
Total Gates: 30 (19 from Phase 1A + 11 from Phase 1B)
Expanded concessions program
New on-airport roadway system
Large parking plaza
Construction Impact
Immediate Changes (Starting September 8, 2025)
Closure of arrivals roadway connecting Terminals 1 and 2
Implementation of designated on-airport detour routes
Detailed navigation maps and animated detour videos provided
Ongoing Impacts Through 2028
Continuous detours and temporary routing changes
Gate shuffles and temporary airline relocations
Active coordination of aircraft movements and taxiways during demolition
Funding Structure
Total Program Value: Approximately $3.8 billion
Funding Sources:
Federal grants (including specific Phase 1B grant)
Airport financing
Multiple funding streams
