Across the United States, cities continue to invest in improved and expanded fixed-guideway transit—public transportation investments designed to substantially improve the speed and reliability of bus and rail options. Nationwide, as I write this, there are under construction 138 kilometers of new light rail or streetcar lines; 34 kilometers of new metro lines; 310 kilometers of new and improved bus lines; and 234 kilometers of regional rail or commuter rail. Many of those projects are expected to open in 2025.
Here, I review the status of transit construction throughout the United States in historical context. I then provide details on what fixed-guideway investments opened in 2024, and which are expected to open in 2025.
This post is based on data compiled on Transit Explorer, the interactive website that assembles information about existing and planned fixed-guideway transit around the world. At the end of this post, find a full list and description of US fixed-guideway transit projects that opened in 2024—plus those planned for opening in 2025. A global roundup of transit openings and planned projects for 2025 can be found here.
The status of transit expansion in the United States
Cities throughout the United States opened very little transit in 2024, adding just 29 kilometers (18 miles) of light rail and no new metro rail service. Though Seattle added some notable new expansions—including an extension north to Lynnwood of its successful light rail route and the first phase of a second line to Bellevue—the only other US light rail expansions were short additions in Los Angeles and Phoenix.
That slow completion rate reflected a broad shift to other types of investments, with a notably increase in investment in bus rapid transit (BRT) lines, including new corridors that opened in Indianapolis, Madison, and Seattle. The rate of BRT investments will increase in the coming years thanks in part to large investments funded by voter-supported referenda, such as those that passed last November in Columbus and Nashville.
Despite 2024’s trend, the United States experienced a modest increase in urban rail transit construction over the past four years compared to the previous period, with about 130 kilometers (81 miles) of new metro, light rail, and streetcar lines opening during the Biden Administration, up from fewer than 100 kilometers during the Trump Administration—the lowest level since the 1970s. But transit is still expanding across the country at a far lower rate than it was during the Clinton, Bush, and Obama Administrations (1993–2016). And the opening of new metro lines, in the form of subways and elevateds, has slowed even further from the heights of the 1970s and 1980s.
In the coming years, the most substantial light rail or streetcar expansion projects are coming to just a few cities. In 2025, Kansas City will more than double the length of its Main Street streetcar line. Los Angeles will add new mileage to its A Line, reaching Pomona; south of LA, Orange County will open a new streetcar line. In Phoenix, the South Central Corridor will create a branch for the city’s light rail route. Finally, in Seattle, the city’s Line 2 will extend north to Redmond and west from Bellevue into downtown Seattle. This will substantially increase the length and usefulness of one of the—or even the—most successful light rail system in the nation.
The Purple Line in the Maryland suburbs of Washington, DC is the other large light rail project now under construction, but it’s not expected to open for another two years, after a decade of delays.
Across the nation, Los Angeles, Dallas, the Bay Area, and Portland now have the longest light rail networks by far, each with more than 100 kilometers of such lines already in service. They will remain the leaders in the coming decade.
US cities have mostly given up on expanding their metro systems. One exception to this trend is Honolulu, whose Skyline automated light metro opened in 2023 and which is expected to expand past the airport in 2025 (making it more useful than the current line, which doesn’t serve major business districts—but the line isn’t projected to extend into downtown until 2031). Also in 2025, Los Angeles will extend its D Line (Purple) subway service into the Mid-Wilshire district, the first of three D Line expansions planned in the coming years.
It is worth noting that there are a few other metro expansion projects in the pipeline, including New York City’s Second Avenue Subway to 125th Street and the extension of Chicago’s Red Line south to 130th Street, which was approved for federal funding in the last few days of 2024 by the lame-duck Biden Administration. A BART extension into downtown San José, on the south side of the Bay Area, is planned. But the other US cities with major metro networks, including Atlanta, Boston, Miami, Philadelphia, and Washington, DC, have no metro expansion projects anywhere close to implementation.
US cities have been far more enthusiastic about investing in bus service. In 2025, Atlanta and Austin will each open improved bus routes, in each case funded by voter-approved referenda. And Minneapolis will add its new B Line, an improved bus line with substantial dedicated lanes.
Finally, both Boston and Chicago will extend their commuter rail networks to serve new destinations.
Below, find a full list of all transit expansion projects that opened in the United States in 2024 and that are expected to open in 2025. And consult Transit Explorer to explore existing, under construction, and planned transit projects globally.
Projects that opened in 2024
Chicago IL: Northwest Indiana Double Track Project, 41.5 km (Commuter Rail). This is not a new line, but the doubling of tracks along the South Shore Line to enable improved service to and from Chicago. This improvement will also enable better service on the West Lake Line, planned to open in 2025 (see below).
Indianapolis IN: Purple Line, 16 km (Bus Rapid Transit). This is the city’s second bus rapid transit line, heading off from the Red Line to the northeast.
Los Angeles CA: K Line (Crenshaw Line) Phase 2 Aviation/Century, 2.3 km (Light Rail). This is a short extension that is the first phase of a route that will connect with the LAX Airport transit center in 2025.
Madison WI: Madison Rapid Route A (East-West BRT), 26.7 km (Bus Rapid Transit). This is the city’s first rapid transit route, offering 15-minute service on electric buses throughout most of the day. Much of the corridor features bus-only lanes and traffic signal priority. Portions of other lines, Rapid Routes B and F, share station stops.
Miami FL: Downtown Miami Link, 14.3 km (Commuter Rail). This is a route that finally connects the city’s Tri-Rail commuter rail system to downtown; it leverages the new elevated station and tracks built for the Brightline intercity rail service. The service previously terminated at Miami-Dade Airport.
Orlando FL: SunRail Phase 2 (North), 19 km (Regional Rail). This is an expansion of the city’s north-south regional rail line. The extension added one new station at DeLand, north from the previous terminus at DeBary.
Phoenix AZ: Northwest Phase 2, 2.5 km (Light Rail). This extends the city’s light rail line to the northwest. The line now terminates at the former site of the MetroCenter Mall.
Seattle WA: Line 1 (Lynnwood Link), 13.7 km (Light Rail). This route adds several new stations to the north along Seattle’s Line 1 light rail service. Eventually, the line is planned to be extended north to Everett thanks to funding approved by voters in 2016.
Seattle WA: Line 2 (East Link) South Bellevue–Redmond Technology, 10.1 km (Light Rail). This is the first phase of the Line 2 light rail service; the connection to downtown Seattle will be implemented in 2025 (see below). This segment includes the line through downtown Bellevue, a major suburban business district.
Seattle WA: RapidRide G (Madison Street), 4.6 km (Bus Rapid Transit). This is a line that runs northeast from downtown, and includes substantial segments of roadway with dedicated lanes for bus service.
Seattle WA: Swift Orange Line, 17.8 km (Arterial Rapid Transit). This adds a new bus service to Snohomish County, north of Seattle. This is the third Swift Line operated by Community Transit, and it links the city of Mill Creek with the newly opened Lynnwood City Center station on Link Line 1 (see above).
Seattle WA: Swift Blue Line Extension, 2.6 km (Bus Rapid Transit). This project expands a service operated by Community Transit in Snohomish County south from Aurora Village to connect with the Shoreline North/185th Street station on Link Line 1 (see above).
Projects that are planned for opening in 2025
Atlanta GA: MARTA Rapid Summerhill line, 5.4 km (Bus Rapid Transit). This new line will make for Atlanta’s most substantial new transit investments in decades, funded by the MORE MARTA sales tax referendum voters passed in 2016. It will be the city’s first BRT investment. The Rapid Summerhill line will run on mostly dedicated lanes south from downtown along Hank Aaron Drive to the Beltline.
Atlanta GA: Cleveland Avenue and Metropolitan Parkway lines, 15.1 km total (Arterial Rapid Transit). Also funded by MORE MARTA, these are more modest improvements than the Summerhill BRT project, both featuring more frequent service and improved bus stops compared to existing service. The Cleveland Avenue line will run east-west, connecting to the East Point MARTA rail station. The Metropolitan Parkway line will run north-south, connecting to the West End MARTA rail station.
Austin TX: Expo Center and Pleasant Valley lines, 42.9 km total (Arterial Rapid Transit). These two improved bus routes are the first major investments to come after Austin voters passed Project Connect, a referendum funding transit, in 2020. The Expo Center line (Rapid 837) will run from Republic Square northeast to the city’s Expo Center; the Pleasant Valley Line (Rapid 800) will run north-south from the Mueller neighborhood to Easton Park. Though services will be implemented in 2025, final improvements are planned for 2026.
Bay Area CA: SMART Train Phase 2 to Windsor, 4.9 km (Regional Rail). This one-station extension will add a northerly terminus for the Sonoma-Marin Area Rail Transit (SMART) line, which opened for service in 2017.
Boston MA: South Coast Rail Phase 1, 60.4 km (Commuter Rail). This project will extend the MBTA’s commuter rail network with new service to Fall River and New Bedford, both south of Boston. The phase of the project opening in 2025 will use Middleborough Line tracks to reach Boston. A second phase, which would provide a faster service to Boston via Stoughton, has yet to be funded.
Chicago IL: West Lake Corridor, 12.8 km (Commuter Rail). This project will extend the South Shore Line through Lake County, Indiana, creating a new service from Munster and Hammond to Chicago’s Millennium Station.
Honolulu HI: Skyline Aloha Stadium–Middle Street, 8.1 km (Metro). This project will extend Honolulu’s automated Skyline light metro, whose first phase opened in 2023 from Kualaka’i (East Kapolei) to Halawa (Aloha Stadium). The extension will service Pearl Harbor Navy base and the city’s airport before terminating at Middle Street, west of downtown. The extension of the line into downtown, also under construction, is not expected to open until 2031.
Kansas City MO: Main Street Streetcar Extension to UMO-KC, 5.7 km (Streetcar). This project will extend the city’s existing streetcar line (which opened in 2016) from Union Station to the University of Missouri at Kansas City. The project is funded by a special tax district and a federal grant. The existing line is already one of the most well-used streetcar lines in the United States.
Los Angeles CA: D Line (Purple) Extension Phase 1, 6 km (Metro). This project will extend Los Angeles’ subway for the first time since 1996, adding three new stations to the west, from Wilshire and Western Avenues to Wilshire and La Cienega Avenues. Additional extensions to Century City and the city’s VA Hospital are expected to open in 2026 and 2027, respectively. Eventually, the D Line is expected to be the city’s most-used transit line, as it serves the densely populated west side of the city.
Los Angeles CA: A Line (Gold Line Phase 2B to Pomona), 14.9 km (Light Rail). This project will extend the A Line from suburban Azusa to Pomona, to the east. With service as far south to Long Beach, the A Line is already the longest light rail line in the world; with the Pomona extension, it will reach 93 kilometers. By 2030, the line is to be extended further east, to Montclair in San Bernardino County.
Los Angeles CA: K Line (Crenshaw Line) Phase 3 LAX/Metro Transit Center, 1.6 km (Light Rail). This extension will connect both ends of the K Line, allowing through service from the Expo/Crenshaw station to Redondo Beach, via LAX Airport. An automated people mover linking the LAX Station with the airport is planned to open in 2026.
Los Angeles CA: OC Streetcar, 7.7 km (Streetcar). This project will serve the Orange County cities of Santa Ana and Garden Grove. The line partially follows the route of the Pacific Electric railway’s Santa Ana Line, which ended service in 1950. As a result, unlike many other streetcar lines in the United States (which share space with cars), the project includes substantial sections with dedicated right-of-way.
Miami FL: South Dade TransitWay Corridor, 31.2 km (Bus Rapid Transit). This line will extend south from the Metrorail terminal at Dadeland South into the southern portions of the county. The line opened for service in 1997, but with this project, Miami-Dade County is substantially improving the system’s speed, comfort, and reliability through improved stations, fare gates, all-door boarding, and signal preemption.
Phoenix AZ: South Central Corridor, 9.4 km (Light Rail). This project will create a new light rail branch, connected to the city’s existing route, along a north-south link on Central Avenue. It will link downtown with South Phoenix.
Seattle WA: Line 2 (East Link) South Bellevue–Stadium, 12 km (Light Rail). This project will connect Bellevue and downtown Seattle via a bridge over Lake Washington. The project is expected to substantially increase overall Seattle light rail ridership, which now averages more than 100,000 riders a day on Line 1 alone. Line 2 is expected to carry 50,000 riders daily.
Seattle WA: Line 2 (Downtown Redmond Link Extension), 5.4 km (Light Rail). This is a further extension of Line 2, whose first segment opened last year. Passengers will be able to ride directly from downtown Redmond to Seattle and then north to Lynnwood.
Twin Cities MN: Gold Line (formerly known as Gateway Corridor), 18.2 km (Bus Rapid Transit). This will be Minnesota’s first BRT project that operates primarily in dedicated bus lanes (unlike the B Line, for example; see below). The route will extend east from downtown St. Paul to Maplewood and Woodbury, serving the headquarters of 3M. In 2027, the route will be extended to downtown Minneapolis via lanes on I-94.
Twin Cities MN: B Line, 18.8 km (Arterial/Bus Rapid Transit). This east-west corridor will connect Uptown Minneapolis with downtown St. Paul, along Lake Street, Marshall Avenue, and Selby Avenue. The project will include dedicated bus lanes along much of the corridor, as well as improved (but fewer) stations compared to the existing bus line, and thus faster service, plus reduced headways between buses.
Note: Dallas’ Silver Line, a regional rail link connecting north Dallas County and DFW Airport, may open in 2025 or 2026; as a result of this uncertainty, I have not listed it above. It is of course worth noting that all infrastructure projects may face delays in opening. Update January 7: The first version of this post incorrectly noted that the B Line in the Twin Cities will not have dedicated bus lanes. In fact it will, along much of its route!
12 replies on “Transit Expansion in the United States: A 2024 Roundup and a Look Ahead to 2025”
Great summary, thanks!
I don’t know if I would call the Gold Line in Minneapolis-St Paul as that region’s first true BRT. The University of Minnesota Transitway provides bus only guideway, two types of signal pre-emption, and since it is free it is quick boarding. Another cool thing about that transitway is that it is used to serve the Minnesota State Fair allowing buses from across the region quick access to the fair grounds and carry something like 40,000+ riders a day each day for 12 days.
San Juan PR is also more seriously studying extension of the Tren Urbano. We’ll see if it leads anywhere.
An argument could be made that the electrification of Caltrain should be included in the list of 2024 projects. Though it doesn’t extend the route, it dramatically increases speed and frequency of service. (Somewhat like the Miami South Dade Transitway which you do include in the list of projects for 2025, and the South Shore Line Double Track Project of last year.)
+1 for including Caltrain electrification. It’s a really transformative project, enabling a standard commuter-rail line to transition to a faster, more frequent metro-style service.
Enjoyed reading, thank you. I wonder how Europe faired and will fair in 2025.
Yonah, thanks for these annual Transit Expansion posts. I especially like that you’ve broken them out by US and non-US posts, makes for more readable, less overwhelming articles.
Thanks for the great update and trove of awesome data! One critique: You group the Maryland Purple Line light rail that’s under construction as part of Washington DC, however, the line is entirely in Maryland, is being built by Maryland rather than WMATA, and will be operated by Maryland’s Dept of Transportation (which runs Baltimore’s transit) rather than WMATA (which runs DC’s Metro system). It’s true that the Purple Line will serve the DC suburbs in Maryland, but for data collection purposes, this project is designed, executed, and paid for by Maryland, not Washington DC.
Yes, all of that is true, but the above list is by metropolitan area, so I’m using Washington, DC as the shorthand for the metropolitan area.
Thank you for this fantastic roundup! It’s impressive to see how many U.S. cities are finally pushing ahead with better BRT and light rail investments. I’m especially excited about the Seattle and LA expansions – both seem like solid steps toward more useful, connected systems ✨
It’s interesting (and a bit sad) to see how metro construction has slowed almost everywhere except Honolulu and LA. Hopefully more cities will prioritize transit that truly expands access, not just short symbolic lines.
eally enjoyed this article – thank you for compiling such a detailed update! It’s always fascinating to compare the pace of transit development in the U.S. with what we see in Europe. I live in Austria, where even small towns are often connected by reliable trains and buses. In Vienna, you can cross the city faster by tram or U-Bahn than by car on most days.
That’s why I created my site https://austriabyoeffis.at – to help both locals and travelers explore Austria using public transport. If you’re ever curious how it works here or just want ideas for car-free day trips from Vienna, feel free to have a look!
I’m really hoping U.S. cities continue investing in full, connected transit networks – not just fragments. The projects coming in 2025 give me some hope.
As 2025 draws to a close, most of the projects listed as opening in 2025 did not in fact open in 2025! Something is seriously wrong with transit planning and construction in this country. We aren’t building much anymore. What we do build is extremely expensive and underwhelming.