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A landmark joint announcement on March 30 from the federal, provincial, and municipal governments made headlines for its funding of the long-delayed Waterfront East LRT, but in amongst other infrastructure plans that were also advanced was a long-standing proposal for a new east-west GO Transit line through central Toronto, part of a larger rail expansion plan known as "GO 2.0". Vague references to the future high-speed Alto's Toronto connections were also made. While more route details remain to be seen, the GO update in particular follows the provincial government's initial proposal of the GO 2.0 plan in February 2025.
On March 30, Prime Minister Carney, Premier Ford, and Mayor Chow appeared together to announce a slew of new funding for housing and transportation initiatives across Ontario. Labelled the "Canada-Ontario Partnership to Build," this multi-billion dollar plan garnered major attention for its changes to the way in which new housing is taxed, seeking to reduce costs at a time of crisis in Canada’s housing sector. In addition, major news around long-speculated commuter rail expansion in the Greater Toronto Area also received formal, though still vague, support from all three levels of government.
While the City of Toronto mostly focused on the Waterfront East LRT, the Ontario Progressive Conservatives election promise for a series of new GO Transit commuter rail lines from their February, 2025 campaign were dusted off. Building off the ongoing upgrading of the majority of GO Transit's existing rail network, known collectively as "GO Expansion," the GO 2.0 campaign promise sought to expand both service levels and coverage on a scale not seen in decades. A preliminary potential network map displayed two new GO lines, the Bolton line and the Midtown line, which would add more than 50 new kilometres of rail service and over a dozen new stations across the region.
Displayed in light pink on the potential network map below, the Bolton line would utilize the Mactier rail subdivision to service North York, Vaughan, and Caledon. This would bring commuter rail service to poorly connected portions of Northwestern Toronto while also providing transit access to rapidly growing Caledon. Shown in purple, the Midtown line would originate in western Mississauga, interlining with the Milton line before following the North Toronto and Belleville subdivisions to serve Midtown, East York, Scarborough, and Markham.
These new lines would put tens of thousands of more commuters within easy access of rapid transit and facilitate cross-regional trips currently infeasible on transit, or slowed by congestion on 400-series highways. A major roadblock has stood in the way of new rail service along these corridors for generations, however, despite the benefits these lines would bring: with small exceptions, all of the requisite rail corridors for GO 2.0 are owned by the continent-spanning Canadian Pacific Kansas City railway (CPKC). Historically, the freight railroad has been highly resistant to the expansion of passenger service along its rights-of-way and has forced service on the Milton line to remain barebones for decades.
In a Province of Ontario press release published with the March 30 announcement, the government expressed interest in "constructing new bypass tracks in the Milton corridor and new railway service through Toronto. These options will be considered alongside plans to advance the Alto High-Speed Rail line, including connectivity to Pearson Airport."
While not explicit regarding the new tracks, the mention of a "new railway service through Toronto" leaves little room for guessing, as outside of the already extensively served Lakeshore West and East GO lines, no rail line travels through the width of Toronto other than the proposed Midtown line corridor. As well, the western portion of the Midtown line would run along the Milton line's current alignment, so the introduction of increased service on the existing corridor would almost certainly necessitate new tracks, "bypass" or not, to the west.
How much new track on the section through Midtown Toronto, though, would depend upon the approach taken to freight traffic in a better use of rail corridor land in and around Toronto: while the aforementioned corridors are the only ones that run through the formal City of Toronto, a freight diversion away from Midtown becomes a possibility if one takes a broader view of what constitutes Toronto, and includes other municipalities of the Greater Toronto Area.
Owned by Canadian National (CN), the York and Halton subdivisions run mostly just north of Steeles Avenue across the width of Toronto through Vaughan and Markham. Initially constructed in the mid-20th century to remove freight traffic from what is now the Union Station Rail Corridor, the line has been contemplated for widening and new connections to also accommodate CPKC. Were quadruple-tracking to happen here, the capacity improvements could allow for the removal of freight rail through-traffic from Toronto's urban core, thereby freeing up Midtown rail capacity for passenger trains.
With so little detail available at this time though, nothing is certain. A non-zero possibility that the historically more collaborative CN could agree to a rebuild that would allow CPKC freight traffic to shift north and free up capacity on the Midtown line is a tantalizing idea if a challenge to realize.
Assuming a GO Midtown line on the North Toronto sub would be served similarly to existing all-day, two-way GO lines, the line holds the potential to revolutionize crosstown (or rather, cross-region) travel in the GTA. As Toronto's downtown and suburban centres continue to densify, the demand for rapid travel between these destinations will only grow. GO service could absorb that demand by providing high-capacity, high-speed travel into and across the central city. Long trips currently taken on relatively slow, stop-heavy subways could be replaced by drastically faster GO commutes. This would be facilitated by transfers at integrated stations where the rail corridor meets the existing subway network, such as at Kipling, Dupont, and Summerhill stations.
The potential upsides are undoubtedly significant, but if and when concrete plans for the city-wide infrastructure upgrades needed to facilitate passenger service are presented, pushback can be expected. Over the last twenty years of growth, swaths of formerly industrial and commercial lands around much of the potential corridor have densified. This is particularly evident where the rail line runs directly north of Dundas and Dupont Streets, with dozens of mixed-use developments sprouting up along the route.
Furthermore, if the government's comments regarding Alto High-Speed Rail (HSR) connectivity to Pearson International Airport suggest a direct link, even more drastic upgrades to the Midtown rail corridor may be required if the Alto route comes into Toronto via Peterborough, as preliminary studies suggest. High-speed rail typically operates within a completely isolated and fully grade-separated corridor to avoid conflicts with road vehicles, as well as slower commuter or freight trains. Both types of train traffic currently use the Weston, North Toronto, and Belleville subdivisions—the three rail corridors providing the most direct link to Pearson from Toronto’s eastern approach. Side-by-side tracks for much of the route is a possibility, but it is also possible that the construction of a new viaduct along parts of this corridor, potentially elevated over the existing rail lines, could be one way for Alto to bypass grade and traffic concerns, and further increase corridor capacity. Elevated sections, however, could prompt protest from nearby residents.
As GO Expansion — the currently in place plan which might now be aptly described as "GO 1.0" — continues to grapple with more than a decade of delays in delivering core infrastructure like electrification and new stations, the capacity for the Province and Metrolinx to manage additional region-wide projects is strained without some radical infrastructure interventions. It remains to be seen how a fresh wave of governmental enthusiasm, coming with funding that exceeds the existing $27 billion budget, will translate into meaningful improvements for travel patterns across the GTA.
UrbanToronto will continue to follow progress on GO 2.0, but in the meantime, you can learn more about it from our Database files, linked below. If you'd like, you can join in on the conversation in the associated Alto HSR and GO 2.0 Forum threads, or leave a comment in the space provided on this page.
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UrbanToronto has a research service, UTPro, that provides comprehensive data on development projects in the Greater Golden Horseshoe — from proposal through to completion. We also offer Instant Reports, downloadable snapshots based on location, and a daily subscription newsletter, New Development Insider, that tracks projects from initial application.
