Introduced in 1997, the Citaro is available in a range of configurations, and is in widespread use throughout Europe and parts of Asia, with more than 55,000 produced by December 2019.

In 2006 the Citaro received a much more substantial facelift, which can be seen from the outside by a revised front and rear design (analogous to the recently introduced low-entry buses).

[5] [6] The standard urban model is available in a number of versions: A series of suburban/interurban versions is also produced, with single front doors and all seats fitted on platforms: Operators are able to choose between two different front stylings: the standard design features an angled destination display, like a roof dome, and is primarily marketed for urban buses, while a version with a one-piece windscreen covering the destination display also is available and is primarily intended for interurban use.

With the introduction of second generation Citaro, the front destination display was slightly enlarged, which juts a bit out of the vehicle roof.

Later, after the introduction of Euro VI version, which results a complete structural change in engine compartment, also the rear destination display was enlarged and added with a fairing.

[7] As a one-off, German operators üstra of Hanover and LVB of Leipzig took delivery of a batch of Citaros bodied to a special design by James Irvine for Expo 2000.

Leipzig's vehicles were lent to Hanover for the duration of the exhibition, but subsequently returned to normal service in their home city.

In 2007 the workshops of the Szeged (Hungary) bus operator SZKT converted a regular Citaro to a trolleybus.

The Mercedes-Benz Citaro G BlueTec Hybrid is a series-hybrid articulated bus with a compact 450 kg, 4-cylinder, 4.8-litre, 160 kW, Euro 4 OM-924LA diesel engine providing power for a roof-mounted 19.4 kWh lithium-ion battery pack, and four 80 kW electric wheel hub motors located on the centre and rear axles.

[9][10][11] In 2010, selected bendy buses were delivered in hybrid version to Wuppertal, Stuttgart, Krefeld, Hamburg and Mülheim.

It uses 14 kW, disc-shaped electric motor mounted between combustion engine and transmission for energy recuperation and can provide a torque of up to 220 Nm.

The vehicle has four wheel hub motors with 60 kW continuous power on the second and third axle and has a range of more than 50 kilometres (30 mi).

The bus features a modular battery pack design and use the same electric wheel hub motors as the Citaro G BlueTec Hybrid.

It uses modified bodywork of standard Citaro with front adopted from Daimler's concept Future Bus.

On 15 November 2018, the first series of eCitaro was delivered to its first customer: Hochbahn AG, a public transport company in Hamburg, with a total of 20 at last.

This was also followed with orders from Verkehrsbetriebe Hamburg-Holstein (VHH) with 16 buses, ESWE Verkehrsgesellschaft mbH from Wiesbaden with 56, and ÜSTRA from Hannover with 48.

Called the eCitaro K, it featured a 4,398 mm wheelbase and a turning radius of just 17.28 meters, making it suitable for busy city routes.

The eCitaro K is powered by a five high-voltage battery packs with a combined capacity of 491 kWh and delivers a range of 300 km under optimal conditions.

This is expected to save on spare parts inventory - this can be done together with the same diesel buses of the dispenser series - as well as lower acquisition costs compared to standard production trolleybuses.

Mercedes-Benz CapaCity (also known as O530 GL) is a large-capacity articulated bus based on Citaro G, which was introduced in year 2007.

It features exactly the same turning circle as that of its shorter related Citaro G (17.94m length) thanks actively steered electro hydraulic fourth axle.

Several improvements were done for the new Conecto, as well as driving safety, passenger comfort, handling and Euro 6 engines, while the operation costs still stay low.

In Hungary, VT-Arriva purchased 159 to operate services in Budapest for Budapesti Közlekedési Központ (BKK) in 2013, followed by two more units the year after.

In 2010, Empresa de Transportes Gondomarense bought five Citaro K (midi variant) for bus lines with small numbers of passengers.

In 2022, Área Metropolitana de Lisboa (AML) offered 633 Conectos, 157 Intouros and 50 Citaros (all with Euro 6 engines and Voith Diwa 6 gearbox).

In early 2015, the new operator Malta Public Transport loaned 25 ex-Heathrow airside Citaro C1 facelifts for use as city buses from Dawson Group.

From 2020 to 2023 both Athens and Thessaloniki have rented used Citaro buses from PAPADAKIS BROS S.A. that were previously owned by several European bus operators including Connexxion, Qbuzz, BVG and more.

[64][circular reference] In 2006, three hydrogen fuel cell-powered Citaros began trial operations in Beijing, China.

[65][66] In 2010, Keisei Bus ordered 15 articulated O530G Citaro G buses, primarily for service in east Tokyo.

It was deployed only on routes 93 and 272, and was returned to Mercedes-Benz in 2021, which is due to the subsequent transition to the electric Citaro fleet in the future.