Articulated and bi-articulated buses: definitions, length limits and R107 rules

An articulated bus is a bus of rigid sections joined by an articulated section through which passengers move from one section to the next; a bi-articulated bus has two such joints. In the European Union, Directive 96/53/EC defines the articulated bus as two rigid sections connected by an articulated section and allows it 18.75 m in length, but Article 1(3) says the Directive “shall not apply to articulated buses comprising more than one articulated section”. UN Regulation No. 107, on the general construction of buses, defines an articulated vehicle as two or more rigid sections and sets requirements for the joint itself. Of the national texts read, Sweden’s Trafikförordning gives a bus with more than one articulated section 24.0 m and 60 km/h; the German and Dutch texts give an articulated bus 18.75 m. The makers’ documents read give single-joint articulated buses from 17,950 mm to 20,995 mm.

Status as at 9 November 2026. The legal texts and the makers’ documents were read on 8 November 2026; Türkiye’s Highway Traffic Regulation (Karayolları Trafik Yönetmeliği) was read in its consolidated text on 14 November 2026. Directive 96/53/EC is the consolidated text of 14 August 2019, and UN Regulation No. 107 the text published in the Official Journal on 29 January 2026, incorporating the 11 series of amendments. The Swedish Trafikförordning is amended up to SFS 2026:1052. The Dutch Regeling voertuigen is the version valid from 1 January to 30 June 2026; the version in force since 1 July 2026 was not read. The dated data sheets are of April 2026 (Mercedes-Benz) and 15 August 2024 (Volvo).

What makes a bus articulated

Article 2 of Directive 96/53/EC reads: “‘articulated bus’ shall mean a bus consisting of two rigid sections connected to each other by an articulated section.” The passenger compartments of the two sections “shall be intercommunicating”, the articulated section “shall permit the free movement of travellers between the rigid sections”, and “Connection and disconnection of the two sections shall be possible only in a workshop”. Annex I lists a bus with a trailer as a separate entry.

UN Regulation No. 107 applies to “every single-deck, double-deck, rigid or articulated vehicle of category M2 or M3” (paragraph 1.1). An articulated vehicle “consists of two or more rigid sections which articulate relative to one another”; the passenger compartments intercommunicate so that passengers can move freely between them, and the sections can only be separated “by an operation involving facilities which are normally only found in a workshop” (paragraph 2.1.3). A double-decker articulated vehicle intercommunicates “on at least one deck” (paragraph 2.1.3.1); the other two-deck rules are in double-decker buses. For an articulated vehicle the approval forms of Annex 1 ask for the number of seats in each rigid section. The bodywork codes for articulated vehicles are listed in vehicle categories M, N and O.

One articulated section: the EU limits

Point 1.1 of Annex I gives an articulated bus 18.75 m, against 13.50 m for a bus with two axles and 15.00 m for a bus with more than two; a bus with a trailer is also 18.75 m. Bus and coach dimensions sets out how the figure rose from 18.00 m, with the width and height limits. Article 4(1)(b) says Member States “shall not authorise the normal circulation within their territories” of vehicles for national passenger transport that do not conform to points 1.1, 1.2, 1.4a, 1.5 and 1.5a. Article 4(5) lets them allow vehicles “incorporating new technologies or new concepts” which cannot comply with the Directive to carry out “certain local transport operations for a trial period”, informing the Commission.

In the turning test of point 1.5a, “the two rigid portions shall be aligned with the plane” established by a line on the ground before an articulated vehicle drives into the 12.50 m circle; bus and coach dimensions gives the test in full. Annex 11 of UN Regulation No. 107 (paragraph 3.4.2) and Article 5.18.16(5) of the Dutch Regeling voertuigen set the same alignment.

Point 2.4 gives a three-axle articulated bus 28 tonnes, raised by up to 1 tonne for alternative fuel technology and up to 2 tonnes for a zero-emission vehicle. Makers’ gross weights and passenger totals for articulated models are set against it in bus weight and seating capacity.

More than one articulated section

Article 1(3) of the Directive reads: “This Directive shall not apply to articulated buses comprising more than one articulated section.” Directive 2002/7/EC added the paragraph. The Directive gives no length or weight for such a bus.

Sweden’s Trafikförordning names a length. Under 4 kap. 17 a §, a bus may be driven on roads other than private roads (“andra vägar än enskilda”) only if its length does not exceed the figures listed and it meets the turning requirements that Transportstyrelsen, the Swedish Transport Agency, sets. The list gives 13.5 m for a bus with two axles, 15.0 m with more than two, “Ledbuss med en ledad sektion 18,75 meter”, “Ledbuss med fler än en ledad sektion 24,0 meter”, 24.0 m for a bus with a trailer for passenger transport and 18.75 m for a bus with another trailer. Under 17 b §, Transportstyrelsen may issue regulations allowing vehicles to exceed those lengths, on conditions that keep road safety from being endangered, and may limit them to a certain road or road network. Under 17 d §, it may grant permits for a trial period “om det behövs för att pröva ny teknik eller nya konstruktioner” (if this is needed to test new technology or new designs), limited to a certain road or road network.

The speed table of 4 kap. 20 § gives “Ledbuss Med fler än en ledad sektion” 60 km/h, against 90 km/h for a heavy bus, or 100 km/h if everyone older than three years travelling in it has a seat with a seat belt. The section is replaced on 1 December 2026, and the replacing text keeps the three figures. Limits that other countries set for articulated buses are among the national rows of truck and bus speed limits in Europe.

None of the makers’ documents read describes a bus with more than one articulated section. Bi-articulated buses and their figures are in the biggest trucks and buses in the world, and trolleybuses in 12, 18 and 24 m lengths in trolleybuses explained.

National rules

Countries without a row are not covered.

What UN R107 requires at the joint

The table lists what the Regulation sets for an articulated vehicle in particular; paragraphs numbered 7 are in Annex 3. Door and exit counts per section are in bus doors and emergency exits, and the classes in bus classes under R107. For a low-floor vehicle, the share of standing area without steps is measured on the forward section of an articulated vehicle (paragraph 2.1.4), as bus accessibility sets out.

Articulated buses in makers’ documents

The joint. Daimler Buses calls the ATC an anti-jackknife system for articulated buses. Its CapaCity page says the ATC regulates the hydraulic damping of the joint “depending on the steering angle, the angle of the articulation joint, the speed and the load, among other factors”, and that under normal running conditions the joint “runs freely”.

Longer than 18.75 m with one joint. Daimler Buses says the CapaCity and the CapaCity L “manage with just one articulation joint”, and its model page attributes their turning circles, 22.93 m and 24.47 m, to the “electrohydraulically steered fourth axle”. The fourth axle is also actively steered when the bus reverses, and when it pulls away from a stop its steering “reacts to the steering movement of the front axle with a defined delay”. Two side-mounted cameras “positioned directly behind the articulation joint” monitor the rear section. The CapaCity documents read name no country and no permit.

Lengths, weights and seats of other 18 m city buses are on the model pages of the Mercedes-Benz Conecto, Iveco Bus E-Way, Iveco Streetway, Anadolu Isuzu Citiport, Otokar Kent, Karsan e-ATA, Solaris Urbino 18 hydrogen, Ebusco 3.0, BMC Procity and VDL Citea. How the EU CO2 standards group articulated city buses is in city bus propulsion.

Not verified

• Netherlands. The version of the Regeling voertuigen in force since 1 July 2026 was not read.
• MAN Lion’s City 18 and Iveco Bus Urbanway 18 m. MAN’s data sheet gives the Lion’s City 18 as 18,060 mm long with wheelbases of 5,200 mm and 6,680 mm and 2, 3 or 4 doors, and its model overview gives the Lion’s City 18 E as 18.1 m with “Two driven axles, two electric central motors”. Iveco Bus’s sheet gives the Urbanway CNG 18 m as 18,000 mm on a front, middle and rear axle, with wheelbases of 5,355 mm and 6,675 mm, and lists “ECE R107 and R66 compliant”. Neither maker’s document read calls these buses articulated.
• Hess lighTram 25. Hess gives it as 24.7 m long with two steered axles; the page read states neither the number of articulations nor a passenger capacity.