Toronto subway

Excavation on Front Street for the Yonge subway, 1950. The line opened four years later, in 1954.

Canada's first subway, the Yonge subway, opened in 1954 with a length of 7.4 kilometres (4.6 mi). The line ran under or parallel to Yonge Street between Eglinton Avenue and Union station. It replaced the Yonge streetcar line, Canada's first streetcar line. In 1963, the line was extended northwards from Union station under University Avenue to Bloor Street, where it would later connect with the Bloor–Danforth subway (opened in 1966) at the double-deck St. George station. In 1974, the Yonge Street portion of the line was extended from Eglinton station north to Finch station. The Spadina segment of the line was constructed north from St. George station initially to Wilson station in 1978, and in 1996 to Downsview station, renamed Sheppard West in 2017. Part of the Spadina segment runs in the median of Allen Road – an expressway formerly known as the Spadina Expressway – and crosses over Highway 401 on overpasses. Six decades of extensions gave the line a U-shaped route running from its two northern terminals (Finch and Vaughan Metropolitan Centre stations) and looping on its southern end at Union station. The latest extension from Sheppard West to Vaughan opened on December 17, 2017, making the line 38.8 kilometres (24.1 mi) long, over five times its original length.

Opened in 1966, the Bloor–Danforth subway runs east–west under or near Bloor Street and Danforth Avenue. It replaced the Bloor streetcar line (which also served Danforth Avenue). Initially, the subway line ran between Keele station and Woodbine station. In 1968, the line was extended west to Islington station and east to Warden station, and in 1980, it was further extended west to Kipling station and east to Kennedy station.

Opened in 1985, Line 3 (originally the Scarborough RT) was a light metro line running from Kennedy station to McCowan station. The TTC started to construct the line to use Canadian Light Rail Vehicles. However, the TTC was forced to convert to the Intermediate Capacity Transit System technology because the provincial government threatened to cut funding to the organization if it did not. This line was never extended, and in July 2023, the line was shut down pending its dismantling due to a derailment. It is set to be replaced with an extension of Line 2 to Sheppard and McCowan via Scarborough Town Centre.

Don Mills station serves as the terminus for Line 4 Sheppard, a subway line that opened in 2002.

Opened in 2002, the Sheppard subway runs under Sheppard Avenue from Sheppard–Yonge station to Don Mills station. The line was under construction when a change in provincial government threatened to terminate the project, but Mel Lastman, the last mayor of the former City of North York (today part of Toronto), used his influence to save the project. Despite the construction of many high-rise residential buildings along the line since its opening, ridership remains low resulting in a subsidy of $10 per ride. The line was intended to be extended to Scarborough Centre station, but because of the low ridership and the cost of tunnelling, there was a plan to extend rapid transit eastwards from Don Mills station via a surface light rail line, the Sheppard East LRT. However, in April 2019, Premier Doug Ford announced that the provincial government would extend Line 4 Sheppard to McCowan Road at some unspecified time in the future, thus replacing the proposed Sheppard East LRT.[25]

Pieces of a tunnel boring machine extracted during the construction of Line 5 Eglinton, 2017

Metrolinx is funding the 19-kilometre (12 mi) Line 5 Eglinton, a light rail line along Eglinton Avenue. From Mount Dennis in the west to Brentcliffe Road (east of Laird Drive), the line will run almost entirely underground where Eglinton Avenue is generally four to five lanes wide. From east of Brentcliffe Road to Kennedy station, the line will operate on the surface in a reserved median in the middle of Eglinton Avenue, where the street is at least six lanes wide. Building on the surface instead of tunnelling reduces the cost of construction on the eastern end of the line. The average speed of the line is expected to be 28 kilometres per hour (17 mph); as a comparison, the average speed of the heavy-rail Line 2 Bloor–Danforth is 32 kilometres per hour (20 mph). The Eglinton line originated from Transit City, a plan sponsored by then–Toronto mayor David Miller, to expedite transit improvement by building several light rail lines through the lower density parts of the city. Of the light rail lines proposed, only the Eglinton and Finch West lines are under construction as of 2022. Line 5 is expected to be completed in 2024.[12]

Line 6 Finch West, also known as the "Finch West LRT", is an under-construction line being built by Mosaic Transit Group along Finch Avenue.[26][27] It is to be operated by the Toronto Transit Commission and was also part of the Transit City proposal announced on March 16, 2007. The 11-kilometre (6.8 mi), 18-stop line is to extend from Finch West station on Line 1 Yonge–University to the north campus of Humber College. The line is forecast to carry about 14.6 million rides a year or 40,000 a day by 2031. It is scheduled for completion in 2024, with an estimated cost of $1.2 billion. Construction on this line began in 2019.[17]

Ontario Line is an under-construction 15.6-kilometre (9.7 mi) light metro line from Exhibition station to Science Centre station, providing a second rapid transit line through the Financial District and downtown core. Although a subway line along Queen Street was first proposed in the early 1900s, the Downtown Relief Line was first proposed in the mid-1980s. The Ontario Line project extends further west and north than previous proposals to serve more of the city. The line is scheduled for completion in 2031 at a cost of $17 to $19 billion.[18] Upon opening, the plan is for the line is take the "Line 3" moniker formerly used by Line 3 Scarborough.[19]

On March 27, 1963, there was an electrical short in a subway car's motor. The driver decided to continue operating the train, despite visible smoke in the affected car, until the train reached Union station. This decision resulted in the destruction of six subway cars and extensive damage to the tunnel and signal lines west of Union station. Following this incident, safety procedures involving electrical malfunctions and/or fire in subway trains, were revised to improve safety and reduce the likelihood of a similar incident occurring.

On October 14, 1976, arson caused the destruction of four subway cars and damage to Christie station, resulting in the closure of part of the Bloor–Danforth line for three days, and the bypassing of Christie station for some time afterwards for repairs.[28][29]

On August 11, 1995, the TTC suffered the deadliest subway accident in Canadian history, known as the Russell Hill accident, on the Yonge–University line south of St. Clair West station. Halfway between St. Clair West and Dupont stations, a southbound Line 1 subway train hit the rear of a stationary train ahead of it.[30] Three people died and 100 other people were injured, some of them seriously. This led to a major reorganization at the TTC, with more focus on maintaining a "state of good repair" (i.e., an increased emphasis on safety and maintenance of existing TTC capital/services) and less on expansion.[31]

On July 24, 2023, the last car of a train on Line 3 Scarborough derailed south of Ellesmere station. There were 45 people on board, with five injuries reported.[32] The TTC closed the line while the cause of the accident, which was not immediately apparent, was investigated. It announced on August 24 that the line would not reopen.[33]

A Toronto Rocket train using the crossover at Vaughan Metropolitan Centre, a terminal station, to reverse

The heavy-rail subway lines were built in multiple segments with multiple crossovers. These are typically used for reversals at terminal stations, and allow arriving and departing trains to cross to and from the station's farside platform. They are also used for short turning trains at some through stations in order to accommodate emergency and planned service suspensions. Planned service suspensions generally occur on weekends for planned maintenance activities that are impractical to perform overnight.[34] There is only one regular short turn service that occurs during the morning rush hour on Line 1 Yonge–University when some northbound trains short turn at Glencairn station.[35]

On Line 3 Scarborough, light metro trains were not able to switch direction except at the ends of the line as there were no intermediate crossovers between the two termini. Thus, no short turns on Line 3 were possible.

The heavy-rail subway lines use either a one- or two-person crew. With two-person train operation, an on-board train guard at the rear of the train is responsible for opening and closing the subway car doors and making sure no one is trapped in a door as the train leaves a station. From the subway's inception in 1954 to 1991, the train guard notified patrons that the subway car doors were closing with two short blasts from a whistle.[36] With one-person train operation (OPTO), one person operates the train as well as the doors.[37] The TTC notes that modern technology now allows one person to safely operate the train and close the doors, and that OPTO is in use in many major cities with large subway systems such as the London Underground, the Paris Metro, the Chicago "L" and the Montreal Metro.[38]

Subway doors on Line 2 are operated by a train guard, situated in the trailing operator cab.

Initially, all the heavy-rail subway lines (1, 2 and 4) used two-person train operation. On October 9, 2016, Line 4 Sheppard was converted to OPTO.[37] On August 1, 2021, the TTC tested OPTO on a portion of Line 1 on Sundays only. Effective November 21, 2021, the TTC introduced OPTO seven days per week on Line 1 between Vaughan Metropolitan Centre and St. George stations. Between St. George and Finch stations, the TTC continued using two-person train operation[39]^: 00:15:38 until the full conversion of the line to OPTO on November 20, 2022.[40] From its opening in 1985 to its close in 2023, trains on Line 3 Scarborough were operated by one person.

According to a 2020 survey conducted by the Amalgamated Transit Union Local 113, two-thirds of Torontonians surveyed opposed the TTC's plan to eliminate the train guard on Line 1, and three-quarters of Torontonians disapproved of the fact that the public was not consulted when train guards were removed from Line 4's daily operations in 2016, citing safety concerns, among other issues, as key reasons motivating their response.[41][42]

In 1991, as a result of lawsuits, electronic chimes, in the form of a descending arpeggiated major triad and a flashing pair of orange lights above the doorway, added for the hearing impaired, were tested and gradually introduced system-wide during the 1990s. The Toronto Rocket trains use the same door chimes and flashing orange lights as the older trains do, and also plays the additional voice announcement, "Please stand clear of the doors". Those chimes have become synonymous with the TTC and Toronto in general to the point that the CBC Radio One local afternoon show, Here and Now, includes them in its theme music.

There are several basic procedures that need to be completed once a train has entered a station. On TTC's Line 2, several symbols of different colours are installed on the station wall for the crew to use as a reference in positioning the train in the platform. A red circle, located at the train exit end of the platform, should be directly in front of the train operator's cab window when the train is aligned properly. A green triangle, located at the opposite end of the platform, is provided as a reference to the train guard that shows that the train is correctly aligned.[43] Before opening the train doors, the guard lowers the cab window and points their finger out the window toward the green triangle when the cab is lined up with the triangle. If the train is not lined up properly, the guard is not permitted to open the doors.[44]

To operate the doors, the guard is first required to insert and turn a key. This action provides system control to the door control panel. The doors are then opened by pushing buttons. After the doors are opened, the guard is required to stick their head out the cab window to observe passengers boarding and exiting. The train doors remain open for at least 15 seconds.[43]

When the guard determines that boarding is complete, the doors are closed. Electronic chimes and flashing lights are turned on, then the automated announcement "please stand clear of the doors" is played over the train's public address system, and finally the doors are closed. The chimes provide a clear notification and warning to passengers that the doors are closing and are played before the automated announcement is played, because such announcements may not be heard when the station is crowded.[43]

After the doors are closed, the guard provides a signal to the train operator that the train can proceed. The signal is in the form of a green light that turns on inside the operating cab. When the doors are closed, a light turns on in the operating cab. The guard is instructed to visually observe the platform while the train departs the station. The distance for this visual inspection is typically three car lengths. An orange triangle[44] installed on the station wall indicates the location where the guard may stop observing the platform and pull their head back into the cab.[43] This is done to ensure that no passengers are being dragged along by the train.[43]

All staffed subway operations must verify that the train is properly berthed before the doors are opened. At each subway platform, a set of three 15-centimetre-wide (6 in) platform markers are affixed onto the platform wall. The train operator and guard use them to position the train.

An orange circle platform marker was used to assist the train guard as the train departed the station on Line 2 prior to 2017. An example from Line 1's St. Patrick station is pictured.

The current platform markers used for Lines 1, 2, and 4 are as follows:[45][37]

• Circular red disk (Lines 1, 2, and 4)—This marker is typically mounted on the station platform wall to assist the train operator in positioning the train in the station. When the operator's window is aligned with the red disk, the train is properly berthed in the station.
• Green triangle (Lines 1 and 2)—This marker is typically mounted on the station platform wall to indicate to the guard, who is positioned in the trailing car, that it is safe to open the doors. When the guard's window is aligned with this marker, the guard must confirm the stop position by physically pointing to the green triangle. If the guard cannot see the green triangle, they are not permitted to open the train doors.
• Orange triangle (Lines 1 and 2)—This marker is typically mounted on the station platform wall to assist the guard, who is positioned in the trailing car, to observe the platform for the required distance as the train is moving to exit the station. When the guard sees this triangle, they can cease observations. The distance between the green and orange triangles is typically the length of three rail cars.

Prior to 2017, when subway guards operated the doors from the fifth car instead of the trailing car in the T1 trains on Line 2, different platform markers were used. The following markers have now fallen into disuse as a result of a March 2017 policy change[46] that required all guards to work from the trailing car on Line 2:

• Circular green disk (Line 2)—This marker was mounted on the station platform wall in front of the guard's window in the fifth car from the lead unit. It indicated to the guard that the train was properly berthed.[47] The guard was required to point to the circle before opening the doors to confirm the stop position.[48]
• Circular orange disk (Line 2)—This marker was mounted on the station platform wall to indicate to the guard when they could cease train departure platform observations. At this point, the guard closed the cab window.[47]

Service frequencies as of November 20, 2022

Line	Off-peak frequency[5]	Rush hour frequency[5]
Yonge–University	3 min 40 s – 6 min	2 min 50 s
Bloor–Danforth	3 min 45 s – 6 min	3 min
Scarborough	6 min 45 s	5 min
Sheppard	5 min 30 s

During rush hour, up to 65 trains are on Line 1 simultaneously, 45 trains on Line 2, and 4 trains on Line 4. During non-rush hour periods, there are 30–46 trains on Line 1 at any one time.

On weekdays and Saturdays, subway service runs from approximately 6:00 am to 1:30 am; Sunday service begins at 8:00 am. Start times on holidays may vary.

The Toronto Rocket uses orange LED signs to provide visible stop announcements.

On January 8, 1995, train operators began to announce each stop over the train's speaker system as a result of pressure from advocacy groups for the visually impaired, but announcements were sporadic until the TTC began to enforce the policy circa 2005. Later, automated announcements were implemented under further pressure from the advocacy groups.[49][50] All Toronto subway trains use an automated system to announce each station, which is played twice over the speaker system: when the train departs a station (e.g. "The next station is: Dufferin, Dufferin station") and when it arrives at the following station (e.g. "Arriving at: Dufferin, Dufferin station"). In addition, the TTC's Toronto Rocket subway trains provide visible and audible automatic stop announcements. Unlike the other trains, the Toronto Rocket trains also announce connections to other TTC subway lines, such as "Change for Line 2", and terminus stations, "This is a terminal station" where applicable. As of 2015, they also announce, except at terminus stations, which side the train doors will open on at each stop based on the direction of train travel.[50]

Switches and power rails are vulnerable to malfunction under extreme winter conditions such as heavy snow or freezing rain. During such events, the TTC runs "storm trains" overnight along subway lines to keep power rails clear of ice. The TTC also has trains to apply an anti-freeze to the power rail once freezing rain starts.[51]

These precautions were also used on Line 3 Scarborough, which used two power rails.[51] After reviewing operations during the winter of 2018–2019, the TTC decided to change its procedures for Line 3. Thus, about two hours before an expected storm, the TTC would decide whether to shut down Line 3 and replace it with bus service.[52] Just before the storm of February 2, 2022, the TTC replaced all Line 3 trains with 25 buses.[53]

To keep switches in the yards from freezing, crews use switch heaters and manually monitor them to ensure they stay in working order during winter storms. Workcars are run as storm trains within the yards to prevent ice from building up on the power rails.[51] The TTC stores subway trains in tunnels along main lines rather than in exterior yards.[53]

Elevators at the subway platform of Vaughan Metropolitan Centre station

Most of the Toronto subway system was built before wheelchair access was a requirement under the Ontarians with Disabilities Act (ODA). However, all subway stations built since 1996 are equipped with elevators, and seventy percent (56 of 75) of Toronto's subway stations are now accessible following upgrade works to add elevators, wide fare gates, and access doors to station.[55]

All subway stations will be made accessible by 2025.[55] By comparison, the Montreal Metro plans for all stations to be accessible by 2038,[56] the Chicago "L" plans for all stations to be accessible in the 2030s,[57] and the New York City Subway plans for 95 percent of stations to be accessible by 2055.[58]

All TTC trains offer level boarding for customers with wheelchairs and other accessibility needs, with priority seating and dedicated wheelchair areas onboard each train.[59]

The May 2010 TTC cleanliness audit of subway stations found that none of them meets the transit agency's highest standard for cleanliness and general state of repair. Only 21 stations scored in the 70- to 80-percent range in the TTC's cleanliness scale, a range described as "Ordinary Tidiness", while 45 fell in the 60- to 70-percent range achieving what the commission describes as "Casual Inattentiveness". The May audit was the third in a series of comprehensive assessments that began in 2009. The commission announced a "Cleaning Blitz" that would add 30 new temporary cleaners for the latter part of 2010 to address major issues and has other action plans that include more full-time cleaners, and new and more effective ways at addressing station cleanliness.[60][61]

Stained glass artwork Sky Ellipse at Highway 407 station

According to a 1991 CBC report, "aesthetics weren't really a priority" on Toronto's subway system, describing stations as "a series of bathrooms without plumbing".[62] Since that time, Toronto's subway system has had over 40 pieces installed in various subway stations. More art appeared as new stations were built and older ones were renovated.

In 2004, USA Today said of the Sheppard subway line: "Despite the remarkable engineering feats of this metro, known as Sheppard Subway, [it is] the art covering walls, ceilings, and platforms of all five stations that stands out. Each station is 'a total art experience where artists have created imaginative environments, uniquely expressing themes of community, location, and heritage' through panoramic landscapes and ceramic wall murals."[63]

In 2012, the TTC awarded a contract to BAI Communications Canada to design, build and maintain a celular and Wi-Fi system along Toronto subway lines. BAI agreed to pay $25 million to the TTC over a 20-year period for the exclusive rights to provide the service. BAI in turn would sell access to the cellular system to other carriers.[64][65]

On December 13, 2013, Wi-Fi Internet access was launched at Bloor–Yonge and St. George stations. The ad-supported service (branded as "TConnect") was provided by BAI Canada. The TTC and BAI Canada planned to offer TConnect at all underground stations.[64] Commuters had to view a video advertisement to gain access to the Internet.[66] It was expected that all of the 70 subway stations would have service by 2017, as well as the six stations along the Line 1 extension to Vaughan.[67] From early December 2015 to late January 2016, users of TConnect were required to authenticate using a Twitter account, with Twitter's Canadian operations sponsoring the TConnect Wi-Fi network.[68] Users of the network could sign in to enable an automatic Wi-Fi connection for 30 days. This arrangement was resumed on an optional basis from July 2016 to early December 2016. By August 2017, Wi-Fi was available at all existing stations and would be available in all future stations.[69]

On June 17, 2015, the TTC announced that Wind Mobile (later rebranded Freedom Mobile) customers would be able to access cellular connectivity at some TTC subway stations. Service was initially between Bloor–Yonge and St. George stations on Line 1, and between Bloor–Yonge and Spadina stations on Line 2.[70] Other carriers declined to use the BAI cellular system because of the price BAI was asking for access.[65]

In April 2023, Rogers Communications took over BAI Communications. In August 2023, Rogers implemented 5G wireless service at all the TTC's downtown stations and within the tunnels between them.[71] In September 2023, the federal government imposed new licence conditions requiring that cellphone and data services be available on the entire subway network by the end of 2026 and that all carriers, including Telus and Bell, were to have access to it.[71] On October 2, 2023, Bell and Telus offered its cellular customers access to the subway's 5G system.[72]

As of October 2, 2023, all downtown subway stations and some west end stations, as well as the tunnels connecting them, have Rogers 5G wireless service. The service is available to customers of Rogers, Freedom Mobile, Bell and Telus (including flanker brands of these companies such as Koodo and Virgin Plus).[72] 5G wireless service is available between Bloor–Yonge and Dupont stations on Line 1, and between Castle Frank and Keele stations on Line 2.[73] The stations and tunnels between Vaughan Metropolitan Centre station and Sheppard West station on Line 1 have a non-5G service.[74]

The TTC offers Wi-Fi to connect to the Internet at all stations but not in tunnels; this service is ad-supported.[69]

Rosedale station bears the name of the neighbourhood (Rosedale) in which it is located.

The TTC considers multiple different factors when they name stations and stops for subway and LRT stations. They consider local landmarks, the cross streets of the station, distinct communities of the past and present in the vicinity of the station, names of other stations in the system, and the grade of the station.[75]

Metrolinx uses five criteria for naming stations and stops. These are:[76]

1. Simplicity
2. Names must be logical and relevant to the area the station is built in
3. Names should be relevant for the life of the station
4. Names should help passengers locate themselves within the region
5. Uniqueness

Sheppard–Yonge station bears the name of the nearby intersection of Sheppard Avenue and Yonge Street. This station was formerly known as Sheppard station but was renamed in 2002 when Line 4 Sheppard opened.

Metrolinx will use the word "stop" in place of "station" at 10 of the 25 stations along the first phase of Line 5, particularly those that are not grade-separated.[77]

The Toronto Rocket is the newest subway train used by the TTC.

Line 1 Yonge–University and Line 4 Sheppard operate using the newest version of Toronto's subway cars, the Toronto Rocket, while Line 2 Bloor–Danforth uses the older T1 subway trains.[85]

The TTC's original G-series cars were manufactured by the Gloucester Railway Carriage and Wagon Company. All subsequent heavy-rail subway cars were manufactured by Bombardier Transportation or one of its predecessors (Montreal Locomotive Works, Hawker Siddeley, and UTDC). All cars starting with the Hawker Siddeley H series in 1965 have been built in Bombardier's Thunder Bay, Ontario, plant. The final H4 subway cars were retired on January 27, 2012.[86] This was followed by the retirement of the H5 subway cars, which had their final in-service trip on June 14, 2013, and the H6 retirement, which followed one year later with a final run on June 20, 2014.

Following the introduction of the Toronto Rocket trains on Lines 1 and 4, all the T1 trains were moved to Line 2. The T1s were expected to last until 2026.[87][88] By the end of 2019, the TTC had proposed an overhaul to extend the T1 fleet's life by 10 years[89] at an estimated cost of $100 million.[90] By mid-2020, the TTC had started the design phase for a new generation of subway trains to replace the T1 fleet on Line 2 Bloor–Danforth. In late 2021, the TTC expected that the new trains would be introduced between 2026 and 2030,[91] at an estimated cost of $1.6 billion.[92]^: 30 On October 13, 2022, the TTC issued a request for proposals to construct 480 new subway cars (80 six-car train sets) of a design different from the T1 and Toronto Rocket fleet for delivery between 2027 and 2033.[93][94] As of 2022, the TTC plans to overhaul the T1 fleet if newer trains cannot be delivered in time.[90]

An S-series train leaving Kennedy station. The S series is used exclusively on Line 3 Scarborough. The train is photographed in its original livery that was used between 1985 and 2015.

Line 3 Scarborough used 28 S-series trains built by the Urban Transportation Development Corporation (UTDC) in Millhaven, Ontario. These Intermediate Capacity Transit System (ICTS) trains were Mark I models, similar in design to the original trains found on the Vancouver SkyTrain and the Detroit People Mover. These were the original vehicles on the line and were in service from the line's opening in 1985 to its closure in 2023. Because of the trains' age, they were refurbished for operation and initially intended to last until the extension of Line 2 Bloor–Danforth was built. In February 2021, the TTC announced plans to accelerate the retirement of Line 3, intending to close it in 2023. This was due to delays in planning and construction of the Line 2 extension (which was then projected to open in 2030 at the earliest) along with the increasing difficulty of performing critical maintenance work on the trains.[95][96][97] Following an initial temporary closure owing to a derailment in July 2023, the TTC decided in August 2023 not to reopen the line.[98]

The Ontario Line will use smaller train sets and a smaller gauge than those used on the Toronto subway system. By using driverless trains with automatic train control (ATC), Metrolinx expects the line to be as frequent as the existing heavy rail lines despite using smaller, lighter trains. In conjunction with ATC, stations will have platform-edge doors for safety, also allowing riders to exit and enter trains more quickly.[99] The trains will be manufactured by Hitachi Rail, similar to trains in Copenhagen or Rome.[100]

A Bombardier Flexity Freedom LRV being tested on Line 5 Eglinton

Metrolinx plans to use 76 Bombardier Flexity Freedom low-floor, light-rail vehicles for Line 5 Eglinton; however, 44 Alstom Citadis Spirit vehicles may be used if Bombardier is unable to deliver the Flexity Freedom on time. Such a substitution would require modifications to Line 5, especially the maintenance facility, as the Citadis Spirit is longer than the Flexity Freedom. Metrolinx intends to use 17 Citadis Spirit vehicles on Line 6 Finch West instead of the Flexity Freedom.[101]

An interlocking signal used along Lines 2 and 4

Fixed-block signalling was originally used on the Toronto subway since the opening of Toronto's first subway in 1954 and was the first signalling system used on Lines 2 and 4.[104][105] As of 2022, Lines 2 and 4 use fixed-block signalling but Line 1 no longer does. Fixed-block signalling uses automatic signalling to prevent rear-end train collisions, while interlocking signals are used to prevent collisions from conflicting movements on track crossovers.

As of September 24, 2022, automatic train control (ATC) has been implemented along the entire length of Line 1.[106] In 2009, the TTC awarded a contract to Alstom to upgrade the signalling system of the existing section of Line 1, as well as equip its extension into Vaughan, with moving block–based communications-based train control (CBTC) by 2012.[107] The estimated cost to implement ATC on Line 1 was $562 million, $424 million of which was funded by Metrolinx.[104] The first section of the "Urbalis 400" ATC system on Line 1 entered revenue service on December 17, 2017, between Sheppard West and Vaughan stations, in conjunction with the opening of the Toronto–York Spadina subway extension (TYSSE) project.[108]

The benefits of ATC on Line 1 are:

• a reduced headway between trains from 2.5 minutes to 2 minutes during rush hours, allowing a 25 percent increase in the number of trains that can operate[104]
• fewer signal-related delays relative to the old fixed-block system[106]
• more efficient use of electricity, thus reducing operational costs[106]
• allowing single-track, bidirectional operation for trains in passenger service, albeit with reduced frequency, to allow for off-hour maintenance of the opposite track[109][110][111]

The TTC has plans to convert Line 2 to ATC by 2030, subject to the availability of funding.[112]

Line 3 Scarborough was equipped with automatic train control from the outset, using the same SelTrac IS system as Vancouver's SkyTrain, meaning it could be operated autonomously. However, the TTC opted to equip each S-series train with an operator on board for door monitoring.[20]

The future Ontario Line will use automatic train control with driverless trains. Its stations will be equipped with platform screen doors.[113]

When completed, Line 5 Eglinton will use Bombardier Transportation's Cityflo 650 CBTC automatic train control on the underground section of the line between Laird station and Mount Dennis station, along with the Eglinton Maintenance and Storage Facility adjacent to Mount Dennis station.[114]

Schematic of future Toronto subway system after presently under-construction and approved plans are completed in 2030

On April 10, 2019, Ontario premier Doug Ford announced rapid transit–related projects that the Province of Ontario would support with either committed or future financing.[129] One such project is the Ontario Line, a proposed 15.5-kilometre (9.6 mi) rapid transit line that has succeeded the Relief Line proposal. Initially, the project was projected to be completed in 2027,[130] but this was later pushed back to 2030.[131] A groundbreaking ceremony for the Ontario Line was held on March 27, 2022.[132]

The Line 5 West Extension to Pearson Airport is a proposal to extend Line 5 Eglinton from its terminus at Mount Dennis station west along Eglinton Avenue West to the proposed Pearson Transit Hub in Mississauga. In April 2019, Ford said that he would commit funds for this proposal.[133]

The Yonge North Subway Extension (YNSE) is a proposal to extend Line 1 Yonge–University north along Yonge Street from Finch station, the existing terminus of Line 1, to near Highway 7 in Richmond Hill. There would be new stations at Steeles Avenue, Clark Avenue, between Highway 7 and Highway 407 near Langstaff GO Station and Richmond Hill Centre Terminal (dubbed "Bridge station"), and High Tech Road.[134][135] The extension was proposed in the province's 2007 MoveOntario 2020 plan. A major problem with this proposal was that Line 1 was at capacity, and the TTC said in 2016 that the proposed Relief Line and SmartTrack would both need to be in service before opening the YNSE.[136] In 2020, a preliminary agreement was signed between the Ontario provincial government and York Region that anticipated the completion of the extension by approximately 2030.[137]

The Scarborough Subway Extension (SSE) is a proposal to replace Line 3 Scarborough with an eastward extension of Line 2 Bloor–Danforth. On October 8, 2013, Toronto City Council conducted a debate on whether to replace Line 3 with a light rail line or a subway extension. In 2014, the city council voted to extend Line 2 to Scarborough City Centre, which would result in the closure of Line 3.[138][139] The SSE would be 6 kilometres (3.7 mi) long and add one new station to Line 2 at Scarborough Town Centre. TTC and city staff finalized the precise route of the SSE in early 2017.[140] In 2019, the Government of Ontario proposed a modified version of the proposal now known as the Line 2 East Extension (L2EE). The L2EE is 7.8 kilometres (4.8 mi) long and adds three new stations, rather than one.[141] The proposed completion deadline for the project is between 2029 and 2030.[142]

The Line 4 East Extension to McCowan is a proposal to extend Line 4 Sheppard east along Sheppard Avenue East to McCowan Road, where it will connect with the Scarborough Subway Extension. Doug Ford said in April 2019 that he would commit funds related to this proposal.[143]

The Eglinton East LRT is a City of Toronto proposal to construct an LRT line (separate from Line 5 Eglinton) from Kennedy station east to Malvern. This proposal was originally part of the cancelled Scarborough–Malvern LRT in Transit City. It would have stations at Eglinton GO and Guildwood GO, as well as the University of Toronto Scarborough campus.[144]

The Jane LRT is a proposed LRT line that would begin at Jane station on Line 2 and proceed north to Pioneer Village station on Line 1. While initially part of the cancelled Transit City plan, the Jane LRT is part of the 2018–2022 TTC Corporate Plan and tentatively referred to as Line 8.[145]

The Line 4 West Extension to Sheppard West station is a proposal that would extend Line 4 Sheppard west along Sheppard Avenue West to Sheppard West station, where it would link to Line 1 Yonge–University. It is currently listed as an "unfunded future rapid transportation project" in the City of Toronto's 2013 Feeling Congested? report.

The Line 6 East Extension to Finch station is a proposal that would extend Line 6 Finch West east along Finch Avenue West to Finch station, where it would link up with Line 1 Yonge–University. In March 2010, the Ontario government eliminated the proposed section of line between Finch West station and Finch station because of budget constraints. This section of the line was part of the original Transit City proposal. In 2013, this plan was revived as an "unfunded future rapid transit project" in the City of Toronto's Feeling Congested? report, meaning this extension may be constructed sometime in the future. The extension was later shown in the 2018–2022 TTC Corporate Plan with no timeline for completion.

Along with a proposal to extend Line 6 to Finch station, there was another proposal that would have extended the line farther to Don Mills station, where it would have provided a connection to Line 4 Sheppard. In May 2009, Metrolinx proposed that the line be extended from Finch station along Finch Avenue East and Don Mills Road into Don Mills station to connect with the Sheppard East LRT and create a seamless crosstown LRT line in northern Toronto to parallel the Eglinton Crosstown LRT (later designated Line 5 Eglinton) in central Toronto. The TTC said that a planning study would have commenced in 2010.

The Line 6 West Extension to Pearson Airport is a proposal that would extend Line 6 Finch West west to Pearson Airport, where it would provide a link to Line 5 Eglinton. In 2009, the TTC studied the feasibility of potential routings for a future westward extension of the Etobicoke–Finch West LRT to the vicinity of the Woodbine Live development, Woodbine Centre, and Pearson International Airport. This extension was later reclassified as a future transit project as described in the 2013 Feeling Congested? report by the City of Toronto. Metrolinx revealed in January 2020 that they would study a possible connection to the Pearson Transit Hub at Pearson Airport.[146]

The Queen subway line was a subway line first proposed in 1911. When Line 1 was first built, a roughed-in station was included under Queen station, with the intention that the Queen subway would be the city's second subway line. The route of the Queen subway line is included in the routes for both the Relief Line and the Ontario Line proposals.[145]

The Eglinton West line was a proposed subway line in the late 1980s on which construction began in the early 1990s. It was cancelled after the election of Mike Harris as premier of Ontario. Much of its planned route is included in Line 5 Eglinton.[145]

One proposed expansion of Line 2 Bloor–Danforth into Mississauga included eight potential stations stretching west from Kipling station to Mississauga City Centre, retrofitting some existing GO Transit stations. The plan was for the subway stations to open in 2011. Mississauga mayor Hazel McCallion and the Regional Municipality of Peel did not support the project.[147]

The Relief Line was a proposed heavy-rail subway line running from Pape station south to Queen Street East and then west to the vicinity of Toronto City Hall. The proposal included intermediate stations at Sherbourne Street, Sumach Street, Broadview Avenue, and another near Gerrard Square. In January 2016, alignment options and possible stations were still being studied, and the project was unfunded. Construction was expected to take about ten years to complete.[148] As early as 2008, Metrolinx chair Rob MacIsaac expressed the intent to construct the Relief Line to prevent overcrowding along Line 1.[149] Toronto City Council also expressed support for this plan.[150] In April 2019, the Government of Ontario under Doug Ford announced that the Ontario Line would be built instead of the Relief Line. As a result, TTC and City of Toronto staff suspended further planning work on the Relief Line in June 2019.[151]

The Sheppard East LRT was a proposed light rail line running east from Don Mills station to Morningside Avenue in Scarborough. The line was to be 13 kilometres (8.1 mi) long with 25 surface stations and one underground connection at Don Mills station on Line 4 Sheppard. Construction of the Sheppard East LRT was to start upon completion of Line 6 Finch West.[152] However, in July 2016, the Toronto Star reported the Sheppard LRT had been deferred indefinitely.[81] In April 2019, Premier Doug Ford announced that the provincial government would extend Line 4 Sheppard to McCowan Road at some unspecified time in the future, replacing the proposed Sheppard East LRT.[25]

The Don Mills LRT was a proposed LRT line that would have headed north from Pape station along Don Mills to Don Mills station. Its route was later incorporated into the Relief Line and Ontario Line proposals.[145]

• "Transit Toronto Subway Pages". Transit Toronto. Retrieved July 21, 2007.
• Bow, James (June 14, 2007). "Toronto's Lost Subway Stations". Transit Toronto. Retrieved July 21, 2007.
• "Thirty Years down the line". Toronto Star. March 1984. pp. M1, M9.
• Welcome Aboard – Tomorrow's Transit Today – UTDC 1985
• "Rapid Transit Expansion Study (RTES)" (PDF). TTC. August 2001. Archived from the original (PDF) on April 19, 2006.
• "Rapid Transit Expansion Study (RTES) – Follow-Up Report" (PDF). TTC. June 12, 2002. Archived from the original (PDF) on February 21, 2006.
• "Spadina Subway Extension". TTC. 2011. Archived from the original on July 24, 2010.