The capital of São Paulo faces the technical challenge of drilling the ground, erecting monorails and taming digital signaling to finally stitch the metropolis to neighboring municipalities.

Every great city reveals its intelligence by the way it moves people. São Paulo has decided to respond to that sentence with numbers that impress even the most skeptical rail transit technicians.

The São Paulo state government announced a contribution of R$ 57 billion to expand the subway network by approximately 50 kilometers. Added to the R$ 14 billion allocated to 22 kilometers of CPTM metropolitan trains, the package totals 72 kilometers of new tracks and represents the largest investment in subway history in Brazil.

A report by Times Brasil detailed the schedule of simultaneous works covering lines 2-Green, 15-Silver and 17-Gold. The technical heart of the project is the extension of Line 2-Green, which will jump from Vila Prudente to Guarulhos with 13.8 kilometers of track and 13 new stations.

The first phase to Penha has already exceeded 55% execution and includes eight new stations. The second stage will complete the route to Guarulhos with five more stops, integrating the heavy subway network for the first time to a municipality in the metropolitan region that is not the capital.

The budget reserved for this front in 2026 is R$ 2.59 billion, according to a survey published by Exame. The promise of connecting São Paulo to Guarulhos by subway is old, but now it gains financial backing and signed contracts.

While the tunnel boring machine advances in the East Zone’s subsoil, on the surface another equally ambitious project advances with a completely different technology. Line 15-Silver, an elevated monorail that already operates partially, will receive R$ 1.03 billion in 2026 to extend its tracks from Ipiranga to Hospital Cidade Tiradentes.

The monorail is an engineering solution that eliminates the need for deep tunnels and drastically reduces expropriation costs. The elevated track snakes along the central median of avenues, supported by pillars that require less intrusive foundations than conventional underground stations.

To power this expansion, the government secured the purchase of 63 new trains. Of that total, 19 units are monorails for Line 15, of which 15 have already been delivered, and 44 conventional trains will reinforce lines 1-Blue, 2-Green and 3-Red.

The third leg of the investment tripod is Line 17-Gold, a 6.7-kilometer branch with eight stations that will connect Congonhas Airport to Morumbi Station. The inauguration is scheduled for March 2026, ending a wait that has dragged on since the 2014 World Cup.

The Line 17-Gold project was plagued by successive delays, design flaws and changes of contractors. Now, with R$ 836.3 million reserved in this year’s budget, the branch is finally approaching commercial operation and will be operated by the concessionaire Motiva Trilhos.

What makes this works package particularly relevant from a technical point of view is the modernization of control systems. The São Paulo Metro is implementing CBTC (Communication-Based Train Control), a railway signaling architecture that replaces old track circuits with continuous digital communication between trains and control centers.

CBTC makes it possible to reduce the headway between trains without compromising safety, increasing transport capacity without needing to build a single additional kilometer of track. It is the kind of productivity gain that differentiates mature rail systems from underutilized networks.

Along with the new signaling system, the plan includes the installation of platform screen doors at several stations. These glass and metal structures separate the platform from the tracks, eliminating the risk of accidental falls and preventing objects or people from entering the track.

Platform screen doors also have a crucial operational function: by isolating the station environment from the tunnel, they reduce air conditioning dispersion and improve energy efficiency. In systems with CBTC, they are almost mandatory to ensure full automation of train movements.

The financing of this entire machinery relied on legislative authorization for the State to borrow up to US$ 425 million, equivalent to about R$ 2.2 billion. The funds are specifically earmarked for the works on lines 2-Green and 6-Orange, raised from multilateral organizations and international private banks.

Line 6-Orange, incidentally, runs in parallel through a PPP (Public-Private Partnership) with the concessionaire Linha Uni, formed by the Spanish company Acciona. With 15.3 kilometers and 15 underground stations, it will connect Brasilândia to the city center and has a partial operation start scheduled for October 2026.

The governor of São Paulo, Tarcísio de Freitas, sanctioned the law that unlocks the loans in December 2025. The R$ 33 billion package of ongoing subway works in the state is the largest in the historical series and places São Paulo at a level comparable to Asian cities that are expanding their networks at a rapid pace.

The essential difference lies in the financing model. While Chinese cities rely on the state-owned CRRC manufacturing trains and the Chinese state bank providing patient capital, São Paulo needs to tie together international credit, fiscal budget and PPP contracts for each line.

CRRC, the world’s largest train manufacturer, is preparing a factory in Araraquara with an initial investment of R$ 50 million. The unit is expected to produce trains for the São Paulo Metro starting in 2026, signaling that the Brazilian subway expansion is beginning to attract industrial chains to the national territory.

The purchase of 44 conventional trains for the older lines solves a chronic fleet problem. The trains on Line 1-Blue, for example, operate with a high average age, and replacing them with low-floor trains and modernized overhead catenary improves accessibility and reduces energy consumption.

The Line 15-Silver monorail, when completed, will be 13.8 kilometers long and will become one of the largest corridors of this type in the world. The elevated track faces criticism for its capacity limitation compared to heavy subway, but its deployment speed is unmatched in densely occupied urban areas.

The jump of 50 kilometers of subway in the coming years is equivalent to almost half of the entire network built in five decades. The capital of São Paulo today operates just over 100 kilometers of subway lines, a disproportionate number for a metropolis of 20 million inhabitants.

The integration with Guarulhos is the ultimate test of the thesis that the subway can stitch the urban fabric beyond the capital’s municipal limits. If it works, the model could be replicated to other fronts already under study, such as lines 19-Celeste and 20-Pink, which target the ABC region of São Paulo and Osasco.

Brazil arrives in 2026 with a railway paradox: while regional and high-speed train projects stall in licensing and financial unviability, the São Paulo subway advances with a record budget and works measuring up to the largest construction sites in Latin America. The city’s intelligence, after all, is measured by the courage to invest in what really moves people.