# Purple Line (Bangkok)

The MRT Purple line (Thai: รถไฟฟ้ามหานคร สายสีม่วง) or MRT Chalong Ratchadham line (Thai: รถไฟฟ้ามหานคร สายฉลองรัชธรรม) is Bangkok's fifth rapid transit line, following the Sukhumvit Line, Silom Line, MRT Blue Line, and Airport Rail Link. The line is 23 km (14 mi) long, serving the north-western area of Bangkok running from Tao Poon to Khlong Bang Phai in Nonthaburi Province.
The line opened on 6 August 2016. It is the second line of MRT system and is operated by BEM under a concession contract. Daily ridership is 70,000.
A 23.63 km (14.68 mi), 17 station southern extension of the line consisting of a 14.3 km (8.89 mi) underground section and a 9.3 km (5.78 mi) elevated section commenced construction in August 2022. The cost of the southern extension is 82 billion baht and it is planned to open at the end of 2027. By the end of May 2023, construction had progressed to 11.50%. As of December 2024, construction has progressed to 46.3% completion with an expected opening date of 2028.

## Route alignment

The Purple line starts from Khlong Bang Phai station in Bang Bua Thong District. The line travels south along Kanchanaphisek Road before turning eastward near Central WestGate, onto Rattanathibet Road. It continues along Rattanathibet Road, passing through a large residential area in Bang Yai District and crosses the Chao Phraya River on a bridge parallel to the Phra Nang Klao Bridge and runs towards Nonthaburi Civic Center station. The line then turns southward onto Tiwanon Road, passing the Ministry of Public Health and turns southeast onto Krung Thep-Nonthaburi Road, entering Yaek Tiwanon station. The line then enters Bangkok city limits at Bang Sue district and passes Bang Son station before terminating at the upper platforms of Tao Poon station, with a total length of 23 kilometres (14.29 mi), serving 16 stations.

## History

Officially named the Chalong Ratchadham Line (Thai: สายฉลองรัชธรรม) – "To Celebrate the Great King's Reign with Righteousness" – but informally known as the "Purple Line", the rapid transit line provides a north–western corridor in Bangkok's Mass Rapid Transit Master Plan. The line also incorporated an extension of the Blue Line from nearby Bang Sue station to Tao Poon Station.
In the 1990s, the plan for the Purple Line was to run from Bang Phut to Bang Sue for 12 kilometres (7.5 mi), with an extension to Thewet for 6.7 kilometers (4.2 mi).
This line was created from the adjustment of the 1994 mass transit rail system master plan, which connected the original extension of the Blue Line from Tao Poon to Bang Yai, while the original Purple Line would have run from the National Library to Tao Poon and the original Orange Line from Samsen (National Library) to Rat Burana, becoming a new line designated as the Purple Line, included in the master plan of the Office of Transport and Traffic Policy and Planning (OTP) for the first time in 2004. Five years later, the line's construction began.

## Northern section

Construction was divided into six contracts, three of them for civil works. The contracts were signed from late 2009 to early 2010 and completion was originally scheduled for the end of 2014. The third contract included construction of four park and ride buildings at the Khlong Bang Phai, Sam Yaek Bang Yai, Bang Rak Noi Tha It, and Yaek Nonthaburi 1 stations. On 31 March 2017, the fifth contract was effectively terminated and became part of a new Blue Line concession agreement.
The 2011 Thailand floods delayed the construction of the line for nearly 1 year. In June 2013, five people were injured when six beams fell onto vehicles below Tao Poon station. In July 2014, the civil work was 94 percent complete; in October 2014, civil work was stated to be 99% complete.
The line opened on 6 August 2016, when His Majesty King Bhumibol Adulyadej graciously appointed Her Royal Highness Princess Maha Chakri Sirindhorn to represent him in presiding over the opening ceremony and officially pressing the button to open the electric train system. However, the MRT Blue Line extension to Tao poon was delayed, so when it opened the Purple Line couldn't interchange with the Blue line as planned. This resulted in low line usage. Even with a reduced fare, the line only attracted about 22,000 passengers daily compared to a goal of 100,000. A shuttle bus service was in operation between Tao Poon MRT station and Bang Sue MRT station to connect with the Blue Line. When the Blue line extension finally opened a year later, on 11 August 2017, ridership significantly increased. In 2019, daily ridership was 70,000.

### Construction contracts

| Contract | Notes | Contractor(s) | Length (km) |
| 1 | Phra Nang Klao Bridge to Tao Poon | CKTC Joint Venture | 13 |
| 2 | Khlong Bang Phai to Phra Nang Klao Bridge | Sino-Thai Engineering & Construction | 10.75 |
| 3 | Khlong Bang Phai Depot and Park & Ride buildings | PAR Joint Venture | |
| 4 | Purple Line Rolling stocks and O&M | Bangkok Expressway and Metro | |
| 5 | Bang Sue to Tao Poon section and O&M (MRT Blue Line) | Bangkok Expressway and Metro | |
| 6 | Track and Electrical | Italian-Thai Development | |

## Southern section

As the northern section of the Purple line was built first, the 2nd phase of the Purple Line south from Tao Poon via Rattanakosin - Bangkok's old town to Rat Burana would fully complete the line. The length of the southern extension is 23.63 km (14.68 mi) (14.29 km (8.88 mi) underground, 9.34 km (5.80 mi) elevated with 17 stations - ten underground and seven elevated).
The Thai Cabinet was expected to approve the tender in mid 2017 with a tender then to be issued in the second half of 2017. On 25 July 2017, Cabinet approval was given, but the tender was then delayed until 2018. By December 2018, a tender had still not been issued and was further delayed. In August 2019, subject to final land acquisition, a March 2020 tender was planned. In mid 2020, the Ministry of Transport still aimed for a tendering process within 2020 despite COVID-19 related delays. The MRTA then expected to issue a tender in February 2021. and if construction had begun in 2021, the extension was projected to enter service sometime in 2027. However, the tender was delayed yet again and subsequently cancelled in August 2021 until it was finally issued in November 2021.
Construction contracts were signed on 11 March 2022 with a 2005 construction period for an ambitious planned 2027 opening date.

### Construction progress

Contactors were issued with a Notice to Proceed on 25 April 2022 giving them access to sites along the route with actual construction planned to begin from August 2022. Construction began in early August for two contract sections, 3 & 4. Some 410 lots and 500 buildings will need to be appropriated to build the extension and as of May 2022 many of them were still to be surveyed.
Construction progress was at 3.45% complete at the end of September 2022. By the end of November 2022, construction progress was at 4.30%. At the end of February 2023, construction had progressed to 7.73%.
By the end of May 2023, construction had progressed to 11.50%.

### Construction contracts

| Contract | Notes | Contractor(s) | Length (km) | Progress (February 2025) | Cost |
| 1 | Tao Poon to National Library | CKST Joint Venture | 4.8 | 67.56% | ฿19,430 million |
| 2 | National Library to Phan Fah | CKST Joint Venture | 3.44 | 57.94% | ฿15,878 million |
| 3 | Phan Fah to Memorial Bridge | ITD-NWR Joint Venture | 3.1 | 46.47% | ฿15,109 million |
| 4 | Memorial Bridge to Dao Khanong | Unique Construction and Engineering | 4.1 | 50.88% | ฿14,982 million |
| 5 | Dao Khanong to Kru Nai & Depot | Italian-Thai Development | 9 | 28.81% | ฿19,904 million |
| 6 | Track and Electrical | Italian-Thai Development | | 39.01% | ฿3,589 million |
| 7 | Rolling stock | TBA | | TBA | |
| Total Progress | Total Progress | Total Progress | Total Progress | 51.61% | ฿82,083 million |

## Stations

| Code | Station Name | Station Name | Image | Opened | Platform Type | Position | Park & Ride | Transfer | Notes |
| Code | English | Thai | Image | Opened | Platform Type | Position | Park & Ride | Transfer | Notes |
| Khlong Bang Phai - Tao Poon: 20.92 km (operational) ||||||||||
| PP01 | Khlong Bang Phai | คลองบางไผ่ | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | √ | | Exit to: • Khlong Bang Phai Depot • DHL Supply Chain & Distribution |
| PP02 | Talad Bang Yai | ตลาดบางใหญ่ | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | | Exit to: • Big C Extra Bangyai • The Square Bang Yai • Kasemrad International Hospital Ratthanatibeth • Home Pro Rattanathibet • Big C Supercenter Rattanathibet 1 • Decathlon Bangyai • Index Living Mall Bang Yai • Central Westgate • IKEA Bangyai • Bang Yai Market |
| PP03 | Sam Yaek Bang Yai | สามแยกบางใหญ่ | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | √ | | |
| PP04 | Bang Phlu | บางพลู | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | | Exit to Megahome Rattanathibet |
| PP05 | Bang Rak Yai | บางรักใหญ่ | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | | Exit to Wat Bang Rak Yai |
| PP06 | Bang Rak Noi Tha It | บางรักน้อย-ท่าอิฐ | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | √ | Proposed connecting station to BTS (future) | |
| PP07 | Sai Ma | ไทรม้า | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | | |
| PP08 | Phra Nang Klao Bridge | สะพานพระนั่งเกล้า | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | Connecting station, without paid-area integration to Phra Nang Klao pier for • Mine Smart Ferry • CHAOPHRAYA EXPRESS | Exit to: • Wat Noi Nok • Wat Chaeng Sirisamphan • Tonsak Market • Rajamangala University of Technology Suvarnabhumi - Nonthaburi Campus - North Area |
| PP09 | Yaek Nonthaburi 1 | แยกนนทบุรี 1 | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | √ | | Exit to: • Central Rattanathibet • Owl Market |
| PP10 | Bang Krasor | บางกระสอ | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | | Exit to: • Big C Supercenter Rattanathibet 2 • Grand Richmond Stylish Convention Hotel Formerly Si Phon Sawan |
| PP11 | Nonthaburi Civic Center | ศูนย์ราชการนนทบุรี | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | Connecting station, without paid-area integration, to • MRT , via a 350-metre elevated pedestrian walkway. • MRT (future) | Exit to: • National Broadcasting and Telecommunications Commission • Nonthaburi Civic Center • Esplanade Cineplex Ngamwongwan – Khae Rai • Siam Business Administration Nonthaburi Technological College • Makut Rommayasaran Park |
| PP12 | Ministry of Public Health | กระทรวงสาธารณสุข | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | | Exit to: • Ministry of Public Health • Srithanya Hospital • Regional Revenue Office 4 |
| PP13 | Yaek Tiwanon | แยกติวานนท์ | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | | |
| PP14 | Wong Sawang | วงศ์สว่าง | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | | Exit to Big C Market Place Wong Sawang |
| PP15 | Bang Son | บางซ่อน | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | Connecting station, without paid-area integration, to • SRT • SRT Southern Line | Exit to Bang Son Market |
| PP16 | Tao Poon | เตาปูน | | 6 August 2016; 8 years ago (2016-08-06) | Island | Elevated | - | Interchange station to MRT | Exit to: • Tao Poon Market • Lotus's Prachachuen |
| Tao Poon - Kru Nai: 22.78 km (under construction) ||||||||||
| PP17 | Parliament House | รัฐสภา | - | 2029; 4 years' time (2029) (expected) | Island | Underground | - | | Exit to: • Thai Parliament • Defence Industrial Department • 4th Armoured Regiment, 1st Division King's Royal Guard • Air Defence Division • Wat Mai Thongsen • Wat Kaew Fah Chulamanee |
| PP18 | Sri Yan | ศรีย่าน | - | 2029; 4 years' time (2029) (expected) | Stacked | Underground | - | | Exit to: • Supreme Complex • Makro Samsen • Royal Irrigation Department • Medium Irrigation Water Resources Development Division • Wimol Sriyan Commercial College |
| PP19 | Vajira Hospital | วชิรพยาบาล | - | 2029; 4 years' time (2029) (expected) | Stacked | Underground | - | | Exit to: • Vajira Hospital • Sukhothai Palace • Market Place Dusit • Suan Dusit University • Saint Gabriel's College |
| PP20 | National Library | หอสมุดแห่งชาติ | - | 2029; 4 years' time (2029) (expected) | Side | Underground | - | | Exit to: • Suan Sunandha Rajabhat University • The National Library • Rajamangala University of Technology Phra Nakhon |
| PP21 | Bang Khun Phrom | บางขุนพรหม | - | 2029; 4 years' time (2029) (expected) | Stacked | Underground | - | | Exit to: • Bank of Thailand • Bank of Thailand Museum • Bang Khun Phrom Palace • Wat Sam Phraya |
| PP22 | Democracy Monument | อนุสาวรีย์ประชาธิปไตย | - | 2029; 4 years' time (2029) (expected) | Stacked | Underground | - | Interchange station to MRT (under construction) | Exit to: • Mahakan fort • Rattanakosin Exhibition Hall • Queen Sirikit Gallery • Royal Pavilion Mahajetsadabadin • Wat Saket Formerly Phan Fa |
| PP23 | Sam Yot | สามยอด | | 2029; 4 years' time (2029) (expected) | Island | Underground | - | Interchange station to MRT | Exit to: • Khlong Ong Ang • Mega Plaza Saphan Lek • Phahurat • Rommaninat Park • The Old Siam Plaza |
| PP24 | Memorial Bridge | สะพานพุทธฯ | - | 2029; 4 years' time (2029) (expected) | Island | Underground | - | Proposed connecting station to Prachathipok station for MRL | Exit to: • Suksanari School • Wat Prayurawongsawat Worawihan • Wat Phitchaya Yatikaram Worawihan • Wat Anongkharam Worawihan • Nan Ah Hospital • Big C Supercenter Itsaraphap |
| PP25 | Wongwian Yai | วงเวียนใหญ่ | - | 2029; 4 years' time (2029) (expected) | Island | Underground | - | Connecting station, without paid-area integration to • BTS via 270-metre underground walkway • SRT via 120-metre covered walkway (future) | Exit to: • Wongwian Yai Market • Wongwian Yai |
| PP26 | Somdech Phra Pinklao Hospital | โรงพยาบาลสมเด็จพระปิ่นเกล้า | - | 2029; 4 years' time (2029) (expected) | Island | Underground | - | | Exit to: • Somdech Phra Pinklao Hospital • Samre Market Formerly Samre |
| PP27 | Dao Khanong | ดาวคะนอง | - | 2029; 4 years' time (2029) (expected) | Side | Elevated | - | | Exit to: • Big C Supercenter Dao Khanong • Wat Mongkhon Wararam |
| PP28 | Bang Pakaeo | บางปะแก้ว | - | 2029; 4 years' time (2029) (expected) | Side | Elevated | - | | |
| PP29 | Bang Pakok | บางปะกอก | - | 2029; 4 years' time (2029) (expected) | Side | Elevated | √ | | Exit to: • Wat Bang Pakok • Bang Pakok Wittayakom School • Bangpakok 1 Hospital • Bang Pakok Fresh Market • Lotus's Bangpakok |
| PP30 | Yaek Pracha Uthit | แยกประชาอุทิศ | - | 2029; 4 years' time (2029) (expected) | Side | Elevated | - | | Exit to: • Bangkok Employment Office Area 2 • Han Clan Foundation of Thailand • Wat Sarod School • Wat Sarod Formerly Rama 9 Bridge |
| PP31 | Rat Burana | ราษฎร์บูรณะ | - | 2029; 4 years' time (2029) (expected) | Side | Elevated | √ | | |
| PP32 | Phra Pradaeng | พระประแดง | - | 2029; 4 years' time (2029) (expected) | Side | Elevated | - | | Exit to: • Phra Pradaeng Arcade Market • HomePro Suk Sawat • Big C Supercenter Suksawat • Thaiwatsadu Suk Sawat |
| PP33 | Khru Nai | ครุใน | - | 2029; 4 years' time (2029) (expected) | Side | Elevated | - | | Exit to Wat Kru Nai |

## Rolling stock

In November 2013, BEM contracted with Marubeni Corp, Toshiba Corp, and East Japan Railway Company to install E&S systems, supply 21 three-car trains (total of 63 cars) rolling stock, and provide maintenance for 10 years as part of a contract worth 12.6 billion baht. East Japan Railway train manufacturing subsidiary J-TREC built them in Yokohama with the first sets delivered in early 2016. The trains are owned by the MRTA which paid for the rolling stock at BEMs request. The southern extension will acquire 17 additional trains, along with the current ones, to create a total of 38 trains.
In total, line is service by 21 three-car trains. Trains are powered by 750 V DC via third rail system, are air-conditioned and capable of traveling at up to 80 km/h (50 mph).
* MRT Purple Line train entering a station.
* Purple Line train spotted near Central Westgate.
* Interior of a train.
* Interior of a train.
* Dynamic route map
* Platform Level at Bang Phlu station

## Operation
### Headways

MRT Purple Line headway :
| Time | Headway (Minutes:Seconds) |
| Monday - Friday ||
| 05.30 - 06.30 | 07:12 |
| 06:30 - 08:30 | 04:50 |
| 08:30 - 09:30 | 06:25 |
| 09:30 - 17:00 | 08:30 |
| 17:00 - 20:00 | 04:50 |
| 20:00 - 21:00 | 06:25 |
| 21:00 - 24:00 | 09:30 |
| Saturday to Sunday and Public Holiday ||
| 06:00 - 24:00 | 09:30 |

### Ridership

When the Purple line first opened daily ridership was only 22,000 compared to projected numbers of 100,000. After the opening of the Blue Line extension to Tao Poon 1 year later in August 2017, daily average ridership increased significantly from 33,000 to 50,000.
In August 2018, the MRTA Deputy Governor stated that daily ridership had increased to 60,000 each weekday. By late 2019, this had increased to 70,000. In 2023 the purple line saw an average of 50385 passengers per day.
On 16 October 2023, MRT Purple Line began using the new fare rates of 14 to 20 baht (down from 16 to 42 baht) after the '20 Baht Transit Max Fares Policy' was approved by the Thai government.
From January 25 to January 31, 2025, Prime Minister Paetongtarn Shinawatra has implemented a policy of free public transportation in Bangkok for one week. This measure aims to address the worsening air pollution caused by surging dust levels across all districts of the capital.
MRT Purple Line Ridership :
| Year | Quarter | Quarterly Ridership | Daily Ridership | Annual Ridership | Remarks |
| 2016 | Q1 | | | 3,074,389 | |
| 2016 | Q2 | | | 3,074,389 | |
| 2016 | Q3 | 1,161,989 | 20,731 | 3,074,389 | PP01 Khlong Bang Phai - PP16 Tao Poon section opened on 6 August 2016. |
| 2016 | Q4 | 1,912,400 | 20,796 | 3,074,389 | |
| 2017 | Q1 | 1,969,874 | 21,888 | 11,626,990 | |
| 2017 | Q2 | 2,196,900 | 24,142 | 11,626,990 | |
| 2017 | Q3 | 3,437,488 | 37,364 | 11,626,990 | BL10 Tao Poon - BL11 Bang Sue section on MRT Blue Line opened on 11 August 2017. |
| 2017 | Q4 | 4,022,728 | 44,206 | 11,626,990 | |
| 2018 | Q1 | 4,005,632 | 44,508 | 17,644,588 | |
| 2018 | Q2 | 4,120,533 | 45,281 | 17,644,588 | |
| 2018 | Q3 | 4,791,613 | 52,083 | 17,644,588 | |
| 2018 | Q4 | 4,726,810 | 51,379 | 17,644,588 | |
| 2019 | Q1 | 4,699,831 | 52,221 | 19,726,225 | |
| 2019 | Q2 | 4,665,231 | 52,419 | 19,726,225 | |
| 2019 | Q3 | 5,298,016 | 57,588 | 19,726,225 | |
| 2019 | Q4 | 5,063,147 | 55,035 | 19,726,225 | |
| 2020 | Q1 | 4,719,549 | 51,863 | 16,836,638 | 1st wave of COVID-19 outbreaks (January 2020 - May 2020) |
| 2020 | Q2 | 2,208,015 | 24,264 | 16,836,638 | 1st wave of COVID-19 outbreaks (January 2020 - May 2020) |
| 2020 | Q3 | 4,840,866 | 52,619 | 16,836,638 | |
| 2020 | Q4 | 5,068,208 | 55,089 | 16,836,638 | 2nd wave of COVID-19 outbreaks (December 2020 - February 2021) |
| 2021 | Q1 | 3,475,384 | 38,615 | 9,841,934 | 2nd wave of COVID-19 outbreaks (December 2020 - February 2021) |
| 2021 | Q2 | 1,993,392 | 21,668 | 9,841,934 | 3rd wave of COVID-19 outbreaks (April 2021 - June 2021) |
| 2021 | Q3 | 1,417,404 | 15,407 | 9,841,934 | 4th wave of COVID-19 outbreaks (July 2021 - early 2022) |
| 2021 | Q4 | 2,955,754 | 32,128 | 9,841,934 | 4th wave of COVID-19 outbreaks (July 2021 - early 2022) |
| 2022 | Q1 | 2,946,430 | 32,739 | 16,450,757 | 4th wave of COVID-19 outbreaks (July 2021 - early 2022) |
| 2022 | Q2 | 3,569,128 | 39,222 | 16,450,757 | 4th wave of COVID-19 outbreaks (July 2021 - early 2022) |
| 2022 | Q3 | 4,691,107 | 50,991 | 16,450,757 | |
| 2022 | Q4 | 5,244,092 | 57,001 | 16,450,757 | |
| 2023 | Q1 | 5,122,816 | 56,921 | 21,508,224 | |
| 2023 | Q2 | 4,897,809 | 53,823 | 21,508,224 | |
| 2023 | Q3 | 5,623,257 | 61,123 | 21,508,224 | |
| 2023 | Q4 | 5,864,342 | 63,742 | 21,508,224 | Began using 14-20 Baht fare rates from 16 October 2023. |
| 2024 | Q1 | 6,005,239 | 65,992 | 24,675,599 | |
| 2024 | Q2 | 5,718,198 | 62,837 | 24,675,599 | |
| 2024 | Q3 | 6,628,438 | 72,049 | 24,675,599 | |
| 2024 | Q4 | 6,323,724 | 68,737 | 24,675,599 | |
| 2025 | Q1 | 4,245,181 | 71,953 | 4,245,181 | As of February 2025. Free public transportation policy was implemented between 25 to 31 January 2025. |

## Gallery

* Construction site of Khlong Bang Phai depot during 2011 Thailand floods.
* Talad Bang Yai station platform
* MRT Purple Line under construction in 2013.
* View of Krung Thep Aphiwat Central Terminal from the Purple Line platform at Tao Poon station
* Aerial view of MRT Purple Line near Phra Nangklao Bridge.
* Purple Line train approaching Wong Sawang station.
* Khlong Bang Phai depot.
* Purple Line train at Tao Poon station.