MIAL’s reported plan is to move or reduce operations before the winter schedule begins on October 25, freeing Terminal 2 capacity for domestic traffic as T1 is taken out of service. The operator has said airlines may move flights to T2 where capacity exists, shift them to Navi Mumbai International Airport, or temporarily suspend them; it has also said existing Mumbai slot rights would be restored once the rebuilt terminal opens, expected around 2029–30.
On October 1, 2026 MIAL asked airlines asked to begin moving some international operations from T2 to Navi Mumbai Airport. On October 25, 2026 T1 flight operations would cease and domestic traffic is redistributed to T2, NMIA or temporarily suspended.
It appears T1 will stay operational until January. It reports that the first physical redevelopment work begins then, with roughly one-third of T1’s capacity, the north section of T1B, taken down in the opening phase.
MIAL should nevertheless publish a single, airline-by-airline operational notice confirming the final date, terminal and airport for every affected departure. Until it does, passengers should rely on their airline’s booking notice and verify whether their flight departs from BOM Terminal 2 or NMI, Navi Mumbai’s separate airport code.
Terminal 2 can absorb only part of T1’s displaced domestic operation. MIAL’s response has reportedly been to ask airlines to cut or move 265 weekly international flights from October 25, freeing check-in counters, gates, baggage belts and airside capacity for domestic carriers transferred from T1.
The first redevelopment phase is estimated to affect roughly 5 million passengers annually, or about 9 percent of Mumbai airport traffic. That is materially smaller than the roughly 15 million annual passenger disruption implied by a complete immediate T1 shutdown, but the effect could grow as further portions of T1 are removed from service.
This is not simply a terminal swap. To move domestic passengers into T2, MIAL has to create capacity across the entire airport system, including runway slots and ground handling.
IndiGo, SpiceJet, Alliance Air and Star Air are among the carriers reported to operate from T1. Akasa had already moved domestic operations to T2 as part of an earlier realignment. These carriers are expected to shift domestic flights where T2 capacity is available, though final airline-specific schedules have not been fully published.
MIAL has explicitly left airlines the option to move operations to NMIA or temporarily suspend services during redevelopment.
A shift from T2 at Sahar to Navi Mumbai is not a terminal connection. It is an inter-airport transfer between BOM and NMI, with separate airport access, check-in, security and baggage processes. A traveller should not assume an international-to-domestic connection between the two airports is protected unless both flights are on one ticket and the airline explicitly confirms the connection arrangement.
For passengers, the realistic planning rule is to treat a BOM–NMI change as a long landside journey with substantial buffer time. The exact travel time will vary sharply with road congestion, the availability of scheduled shuttle services, rail links and the time of day; no official universal transfer time has been published in the material available here.
IATA had already raised concern about the disruption of forcing airlines and passengers to split operations across Mumbai and Navi Mumbai, particularly when terminal capacity and schedules are being reshaped at short notice. The reported requirement for 265 weekly international flight reductions shows why freeing T2 space for domestic services risks shrinking international connectivity or shifting it to another airport before passengers and airlines are fully ready.
The short-term trade-off is severe but clear. Mumbai is trying to rebuild an ageing domestic terminal while keeping an intensely constrained airport functioning and using NMIA as a pressure valve. The test will be whether MIAL publishes stable, passenger-facing schedules early enough that the network change feels planned rather than chaotic.