Jump to content

Through service

From Wikipedia, the free encyclopedia

A through service is a concept of passenger transport that involves a vehicle travelling between lines, networks or operators on a regularly specified schedule, on which the passenger can remain on board without alighting. It may be in form of either the following:

  • A service where the vehicle travels between different lines, or systems of infrastructure, for example, a through train service between the mainline and underground railways.
  • A service where the vehicle changes its identity en-route without requiring passengers to alight, for example, a through tram service which runs as route 1 initially, then runs as route 2 for the latter half of the journey.

The term through service may be extended to have a wider meaning encompassing a route which allows the passenger to travel without alighting, for example, in a route change announcement, if a route A-B and a route B-C is combined to A-B-C, it may be described as a new "through service" between A and C.[1][2] This is in contrast with direct service, where a through service may be a circuitous route but allows the passenger on board for the whole circuitous journey. This is to be distinguished with operating arrangement which a vehicle changes its service route between revenue journeys at a terminus, but requires passengers to alight or retender fare.

Rail transport[edit]

A train on a through service may also be called a through train[3] (also referred to as through service,[4] run-through service/train[5] or interline[6][7]).

In operational terms, a through train is a train operated on different railway lines, possibly between different operators as well. This is usually accomplished through compatible infrastructure—identical track gauge and durability issues (although variable gauge trains do exist, they tend to be expensive), rolling stock dimensions, curve speed and signaling compatibility, train station dimensions (to avoid damage to rolling stock), tunnels and bridge dimensions and maximum weight, and power requirements. The exact terminology (and definition) vary as usage; in the case of National Rail of the UK, a through train is one which may be used by a passenger to make their entire journey without changing trains.[3]

However, the fact that a train travels on different lines, or even tracks of different operators, may not be obvious if it is operated within the same network from a passenger's perspective. For example, trains in China commonly travel between lines to service different destination, but only when it involves a change of train number as a result of changing from an up-line to another down-line, or vice versa (see below), it is obvious to the passenger.



Mainland China[edit]

In mainland China, as train numbers are decided on the direction (up/down) of track, with up (to Beijing) trains having even train numbers and down (from Beijing) trains having odd train numbers. If a services travel on tracks in different directions, the train number changes at the station where the train changes direction, creating a through service.

For example, the train service from Guangzhou to Lhasa operates between Guangzhou to Zhengzhou as Z264 on the up line, and changes to Z265 from Zhengzhou to Lhasa on the down line, and passengers can stay on board for the whole journey. If a ticket is bought across both section, both train numbers will be shown on the ticket.

Chinese cities operate several through services:

Several metro systems have through operation (simplified Chinese: 贯通运营; traditional Chinese: 貫通運營; pinyin: guàntōng yùnyíng) between lines.

Hong Kong[edit]


Paris Réseau express régional:

  • RER A trains serving the Cergy and Poissy branches run on SNCF (western part) and RATP (eastern part) tracks.
  • RER B runs on SNCF (northern part) and RATP (southern part) tracks.

In both cases, trains run contiguously, thus providing a one-seat ride across both SNCF and RATP networks. To achieve smooth network crossing, RATP and SNCF jointly designed and ordered specific MI 79 rolling stock (where MI stands for matériel d'interconnexion, French for "cross-network rolling stock.") Change of drivers was compulsory at network boundaries until 2008 when one-driver cross-network runs were introduced.


In Germany, such services are called Durchbindung.


A Tokyu Corporation train on the Tobu Isesaki Line. Through service between different suburban rail lines are common in greater Tokyo.

Through services (直通運転, chokutsū unten) are regularly scheduled train services owned by an operator which runs over tracks which it does not own. Many urban railways in Japan operate such services to increase ridership, increase convenience and simplicity, and reduce time to destinations by eliminating transfers through seamless connection. One example is a Narita-to-Haneda Airport Express service, which runs on four companies' tracks-Keikyu, Toei, Keisei, and Hokuso Railway. Despite fewer new lines in recent years as the system is mature, more through services are proliferating to reduce cross metropolitan area connection time, at least in theory.

A 2016 MLIT study has shown that minor train delays are quite commonplace in Greater Tokyo during rush hour, at odds with Japan's image of train punctuality. The reason for this is that the subway lines in particular are subject to heavier loads, and thus more delay as riders rush in at the last minute, and forcing final door closings to be delayed. The proliferation of through-services has only magnified the problem, as it acts as a double-edged sword, though convenient in not having to switch trains, central Tokyo delays increasingly cause a ripple effect to through services on suburban lines.[12]

South Korea[edit]

Subway trains of Seoul Subway Line 1, Line 3 and Line 4 run through to Korail suburban lines. Suin Line and Bundang Line services were merged into the Suin-Bundang Line.


Russia operates regular scheduled through services with other countries:

United Kingdom[edit]

The mainline rail network in Great Britain, with a few exception, is owned and operated by Network Rail which organises its track into lines, such as South West Main Line and East Coast Main Line. A through service on the National Rail network running on the mainline rail is defined as a journey for which a change of train is not required.[3] These trains commonly run through multiple lines of Network Rail for their journey.

In addition, there are also some through service across different infrastructure owners as well, which include:

United States[edit]

In the United States, a through train is referred to as interline and is defined as "the interchange of passengers between one or more bus lines, rail transit lines, or railroads" or "the transfer of transit vehicles or trains between routes during a day to improve staff or vehicle assignment efficiency".[6][7] Examples of interlining include:

Bus transport[edit]

There are some bus services which travel on a route, or a section of it, and change the route number while allowing passengers to stay on board. Such services can be describe as through services.

For example, morebus routes 16 and 17 may operate as a through service through Bournemouth Square, allowing the passenger to stay on board with a through fare.[14]

See also[edit]


  1. ^ "More changes to Yellow Bus routes - is your service affected?".
  2. ^ "New timetables from 28th July - bus routes 271 and 272".
  3. ^ a b c "Archived copy" (PDF). Archived from the original (PDF) on 2013-06-13. Retrieved 2014-11-01.{{cite web}}: CS1 maint: archived copy as title (link)
  4. ^ "Archived copy" (PDF). Archived from the original (PDF) on 2014-11-09. Retrieved 2014-11-01.{{cite web}}: CS1 maint: archived copy as title (link)
  5. ^ "NEC FUTURE: A Rail Investment Plan for the Northeast Corridor: Alternatives".
  6. ^ a b "Compendium of Definitions and Acronyms for Rail Systems" (PDF). American Public Transportation Association. June 20, 2019. p. 109. Retrieved May 10, 2021.
  7. ^ a b "Part 8 Glossary" (PDF). Transit Capacity and Quality of Service Manual (2nd ed.). Transportation Research Board. 2003. pp. 8–21. ISBN 0-309-08776-7. Retrieved May 10, 2021.
  8. ^ "四惠四惠东站无须换乘了!北京地铁1号线、八通线本周日跨线运营". 2021-08-25. Archived from the original on 2021-08-25. Retrieved 2021-08-25.
  9. ^ "缓解客流压力,北京地铁4号线、大兴线调整运营措施". www.xinhuanet.com. Archived from the original on June 17, 2018. Retrieved 2018-06-17.
  10. ^ "北京地铁9号线房山线实现跨线运营". Retrieved 2023-01-21.
  11. ^ "苏州地铁3号线将与11号线贯通运营". 2023-08-16. Archived from the original on 2023-08-20.
  12. ^ "Rush hour delays: Why Tokyo's commuter railways are feeling the strain". 3 April 2018.
  13. ^ Lum, Brian (June 19, 2015). "You asked: How will the Orange Line work in downtown Portland?". TriMet. Archived from the original on October 26, 2015.
  14. ^ morebus 16/17 timetable