The path for the redevelopment and expansion of Terminal 1 (T1) at Mumbai’s Chhatrapati Shivaji Maharaj International Airport (CSMIA) has been cleared, with measures in place to minimise the impact on airline operations.
Following consultations with international airlines, CSMIA has allocated slots to 38 of the 50 international airlines for the Summer 2027 schedule. Twelve airlines, operating around 16 daily departures to 14 destinations, have not been allocated slots at CSMIA from the end of March 2027. These airlines may operate the affected services from Navi Mumbai International Airport (NMIA). The arrangement is expected to leave around 91% of CSMIA’s existing traffic capacity unaffected. Domestic carriers, including IndiGo, Air India and Akasa Air, had already announced plans last week to shift flights serving 14 destinations to NMIA.
The transition is expected to facilitate the movement of around five million passengers annually from CSMIA to NMIA, creating the capacity required for the phased redevelopment of T1. The new terminal will increase T1’s annual passenger handling capacity from the existing 15 million passengers per annum (MPPA) to 20 MPPA. Construction is scheduled to begin in January 2027, with the facility targeted to be operational by March 2029.
The four-level extension will add four domestic bus boarding gates, along with expanded passenger processing, security screening and crew facilities.
The redevelopment is necessary to address structural concerns associated with the ageing terminal while significantly upgrading its infrastructure and passenger-handling capacity. Commissioned in 1964, T1 has a designed capacity of 15 MPPA. Structural audits conducted by Structwel in 2017 and IIT Bombay in 2024 flagged concerns with the existing infrastructure. Demolition is scheduled to begin in April 2027, followed by redevelopment in phases.
CSMIA has assured airlines that their historical slot allocations will be respected and left undisturbed during this temporary transition.