When does the Istanbul M12 metro line open?
Istanbul's M12 Ümraniye-Ataşehir-Göztepe line targets late 2026. Stations, driverless GoA4 operation and construction status here.
Istanbul's M12 metro line (60. Yıl Parkı to Kâzım Karabekir) is a 13-kilometre, 11-station, driverless line linking the Kadıköy, Ataşehir and Ümraniye districts. Istanbul Metropolitan Municipality (İBB) officials say it will open in the last quarter of 2026 (Karar, quoting İBB deputy chair Nuri Aslan).
- Status : date-sensitive (an official target exists, no confirmed opening day)
- Official target : last quarter of 2026 (October to December 2026)
- Last updated : 31 August 2026
- Next expected milestone : end-to-end commissioning test runs across the whole line and a firm opening date from İBB
Why is this line being built?
M12 is meant to close a north-south transit gap between Kadıköy and Ümraniye: riders on this corridor today rely on buses and shared minibuses through congested arterial streets. Once open, the end-to-end journey is expected to take about 21 minutes, with a design capacity of 44,000 passengers per hour per direction (Metro İstanbul, lines under construction page).
The line is being built for fully driverless operation. Alstom signed a contract in February 2022 to install the complete CBTC (communications-based train control) signalling system and the electromechanical infrastructure; the system corresponds to GoA4 (Grade of Automation 4), meaning unattended train operation (UTO) with no driver or on-board attendant (Railway-News on the CBTC contract; RailwayPro on the contract date and scope).
Rolling stock figures have shifted over time. İBB's transport agency, UYM, said in December 2024 that 40 new cars were planned for the line (UYM, 19 December 2024). By August 2026, trade press reported 144 cars, from a larger 272-car order, allocated jointly to the M7 and M12 lines, with the first set in dynamic testing at the Behiç Erkin facility (Taşıma Dünyası Gazetesi, 27 August 2026); public sources do not name a manufacturer for either figure.
Civil works are led by a Gülermak-Nurol joint venture, under a contract signed in April 2017 with an original construction and electromechanical budget of 2.47 billion lira (Rail Turkey TR on the 2017 contract). Since then, currency depreciation and added scope (including the train order) have pushed the reported total cost to 20.1 billion lira (marmaray.istanbul, M12 station and cost summary).
Route, stations and interchanges
The line runs from 60. Yıl Parkı in Kadıköy to Kâzım Karabekir in Ümraniye. Station order and interchanges are as follows (UYM, İBB's own transport agency, official station list; Gazete Kadıköy, interchange confirmation):
| # | Station | District | Interchange |
|---|---|---|---|
| 1 | 60. Yıl Parkı | Kadıköy | Line start |
| 2 | Tütüncü Mehmet Efendi | Kadıköy | Marmaray (Göztepe station) |
| 3 | Sahrayıcedit | Kadıköy | None |
| 4 | Yenisahra | Ataşehir | M4 (Kadıköy to Sabiha Gökçen) |
| 5 | Ataşehir | Ataşehir | None |
| 6 | Finans Merkezi | Ümraniye | M13 (planned, not yet built) |
| 7 | Site | Ümraniye | None |
| 8 | Atakent | Ümraniye | None |
| 9 | Çarşı | Ümraniye | M5 (Üsküdar to Çekmeköy/Sancaktepe) |
| 10 | SBÜ Hastanesi | Ümraniye | None |
| 11 | Kâzım Karabekir | Ümraniye | Line end |
- The Marmaray interchange at Tütüncü Mehmet Efendi is a walking transfer to the existing Göztepe Marmaray station.
- M4 connects at Yenisahra and M5 at Çarşı; both lines are already in service.
- A 900-metre connector tunnel links the section past Finans Merkezi to the M8 line, but it exists to move trains to the Behiç Erkin maintenance depot, not to carry passengers (marmaray.istanbul).
- The M13 interchange marked at Finans Merkezi is for a line that has not been built yet, so it does not exist in practice today.
What riders will notice
When it opens, M12 will fall under the same İstanbulkart fare system used across the rest of the network; there is no indication of a separate ticket or fare model, since the line is designed as part of İBB's existing rail network and is operated by the same company, Metro İstanbul A.Ş. (Metro İstanbul, operator information).
DailyMetro's Istanbul edition is scheduled to launch on 17 September 2026. Once it opens, you will be able to identify a station each day on the real network at DailyMetro Istanbul; its station list will update when M12 enters service.
One benefit of GoA4 driverless operation is frequency: UYM said in December 2024 that the plan called for trains roughly every 5 minutes at peak hours (UYM, 19 December 2024), a planning figure that will not be locked in until commissioning finishes. A bus journey from Kadıköy to Ümraniye that today takes 40 to 50 minutes is meant to drop to about 21 minutes once the line runs (Metro İstanbul). No announcement has been found on cutting existing bus routes on this corridor once M12 opens; that detail is still expected from İBB.
Milestones and delay log
The project's history is not a single delay but a series of funding and payment crises. The verifiable dates, in order:
| Date | Event |
|---|---|
| April 2017 | Construction and electromechanical contract signed with the Gülermak-Nurol joint venture; contract duration 1,020 days, target completion January 2020 (Rail Turkey TR). |
| End of 2018 | Construction halts entirely at roughly 4% physical progress, over funding shortfalls (UYM, retrospective summary, 19 December 2024). |
| 20 October 2019 | New İBB leadership finalises financing talks with the EBRD; work resumes (EBRD, official announcement; Gazete Kadıköy, 19 December 2024). |
| 6 May 2020 | Metro İstanbul announces the then-current target of mid-2022 completion (Metro İstanbul, news page). |
| 9 April 2022 | Press reports say the contractor has not been paid, VAT receivables alone exceed 270 million lira, and work has slowed as a result (emlak365.com.tr). |
| 14 October 2022 | The EBRD adds a further EUR 75 million on top of the 2019 loan (EBRD, official announcement). |
| 14 March 2024 | First test run on the Ataşehir to Finans Merkezi section (Nurol İnşaat, the contractor's own announcement). |
| 5 October 2024 | İBB mayor Ekrem İmamoğlu says the line, 85% complete, will open in October to November 2025 (NTV). |
| 19 December 2024 | Progress reaches roughly 91%; the target is reaffirmed as end of 2025 (UYM, official announcement). |
| 27 December 2024 | İmamoğlu visits Kâzım Karabekir station; progress is stated at roughly 90% (Gazete Kadıköy). |
| March 2025 | Borrowing authorisation for a further EUR 110 million is secured to finish the project, bringing total financing raised to date to EUR 475 million (UYM, official announcement). |
| 12 August 2025 | Progress is stated at 88.2%; İBB says signal testing will be followed by driverless testing, with launch targeted for end of 2026 (UYM, official announcement). |
| 7 April 2026 | İBB deputy chair Nuri Aslan announces progress has reached 97% (Karar). |
| 19 June 2026 | First end-to-end test run runs the Ataşehir to 60. Yıl Parkı section; Ataşehir's deputy mayor states progress at 94% (siyasalyasam.com.tr). |
| August 2026 | The final rail weld is completed; İBB deputy chair Nuri Aslan reaffirms the last-quarter-2026 target (Ataşehir Municipality, official announcement). |
Reported progress is not always consistent: İBB said 97% in April 2026, while Ataşehir Municipality gave 94% in June 2026. That points to no single, continuously published progress metric, not a real regression.
In short: the 2017 contract target was January 2020, and Metro İstanbul's own 2020 target was mid-2022. The line is now approaching completion more than four years past those dates, after at least one full construction halt (end of 2018) and a reported contractor payment dispute (spring 2022).
Independent risk view
As of the date of this article, no published Sayıştay (Turkish Court of Accounts) report specifically covering the M12 line could be located; this section will be updated if one appears. That does not mean the project has not been audited, only that no publicly available, project-specific independent report currently exists.
The project's own record still supports caution. Metro İstanbul's own 2020 target (mid-2022) did not hold, nor did the dates announced afterwards (October to November 2025, then end of 2025); each slid to a new date. Construction stopped entirely at the end of 2018, and press reports in spring 2022 described a contractor payment dispute. Progress figures also do not come from one single source: between April and June 2026, İBB and Ataşehir Municipality gave figures for the same line that differed by several points. So the last-quarter-2026 target, while backed by a high official completion figure, still depends on commissioning tests, including signalling integration and GoA4 verification, going to plan.
Sources
- Karar, İBB statement and current status: trade press report quoting İBB deputy chair Nuri Aslan on the opening target and progress, 7 April 2026.
- Ataşehir Municipality, official news release: local government's own announcement of the final rail weld and progress percentage, August 2026.
- Metro İstanbul, lines under construction page: the operator's own project page.
- Metro İstanbul, 2020 project news item: the operator's own archived news release, giving the target date as of that time.
- EBRD, official loan announcement: the financing institution's own press release, with loan amounts and dates.
- UYM (İBB's transport agency), "New metro cars are coming to Istanbul": official İBB-subsidiary announcement, 19 December 2024.
- UYM, "The countdown continues on the metro line": official İBB-subsidiary announcement, station list and financing update.
- UYM, "İBB nears the finish on the mega project": official İBB-subsidiary announcement, 12 August 2025 progress and testing plan.
- Gazete Kadıköy, "countdown has begun": local press, 19 December 2024.
- Gazete Kadıköy, "opening at the end of 2025": local press, 27 December 2024 site-visit report.
- NTV, İmamoğlu's opening-date statement: national news broadcaster, 5 October 2024.
- Nurol İnşaat, test-run announcement: the contractor's own corporate announcement of the 14 March 2024 test run.
- emlak365.com.tr, payment-dispute report: news report, 9 April 2022.
- siyasalyasam.com.tr, first end-to-end test-run report: local news, 19 June 2026.
- Taşıma Dünyası Gazetesi, rolling-stock report: transport trade press, 27 August 2026.
- RailwayPro, Alstom CBTC contract report: trade press, contract date and scope.
- Railway-News, CBTC and GoA4 technical explainer: trade press, signalling technology detail.
- Rail Turkey TR, 2017 contract and project history: specialist rail press, original contract data.
- marmaray.istanbul, station and cost summary: compiled site, used here for the M8 connector tunnel detail and the current total cost figure.
For more on Istanbul's metro network, see the Istanbul blog.
FAQ
Is the M12 metro line cancelled?
No. As of August 2026 the project is active and İBB has announced that progress has reached 97% with the final rail weld complete (Ataşehir Municipality). Construction stopped entirely at the end of 2018 over funding shortfalls, and press reports in spring 2022 described a contractor payment dispute, but the project was never cancelled (emlak365.com.tr).
When exactly does the M12 metro open?
İBB deputy chair Nuri Aslan has said the line will enter service in the last quarter of 2026, meaning between October and December 2026 (Karar). No exact day has been announced, and given the line's history of repeated date slippage, this target should be read as a range rather than a fixed date.
Which stations are on the M12 line?
The line runs from 60. Yıl Parkı through Tütüncü Mehmet Efendi, Sahrayıcedit, Yenisahra, Ataşehir, Finans Merkezi, Site, Atakent, Çarşı and SBÜ Hastanesi, ending at Kâzım Karabekir: 11 stations in total (UYM, İBB's own transport agency, official station list).
Which lines will M12 connect to?
Riders will be able to transfer to Marmaray at Tütüncü Mehmet Efendi (a walk to the Göztepe Marmaray station), to M4 at Yenisahra, and to M5 at Çarşı. The 900-metre tunnel to M8 is for depot access only, not a passenger interchange (marmaray.istanbul).
Is the M12 metro driverless?
Yes. The line is being built around Alstom's CBTC signalling system for GoA4 operation, meaning fully automatic, driverless, unattended train operation with no on-board staff (Railway-News).
Will my İstanbulkart work on M12?
Yes. The line is part of the existing rail network operated by Metro İstanbul A.Ş., and there is no indication of a separate ticketing system; İstanbulkart is expected to work the same way it does on every other line (Metro İstanbul).
How much does M12 cost and who is paying for it?
The original 2017 construction contract was worth 2.47 billion lira (Rail Turkey TR); the current total cost, including the train order, is reported at 20.1 billion lira (marmaray.istanbul). Alongside İBB's own budget, the project is financed by EBRD loans of EUR 97.5 million in 2019 and a further EUR 75 million added in 2022 (EBRD).