It was introduced in 2005 to replace the Agora. It comes in three varieties: Citelis 10 and Citelis 12, which are standard buses with respectively 10 m (33 ft) and 12 m (39 ft) length, and Citelis 18, which is articulated and has a length of 18 m (59 ft). Citelis models use Euro 4, Euro 5 & EEV engines. The buses can also be built as trolleybuses, utilising overhead electrical wires for their power supply instead of fuel. Trolleybus version of Citelis is also known as Škoda 24Tr Irisbus (12m) or Škoda 25Tr Irisbus (18m), especially in Eastern Europe.
A Citelis 18 CNG chassis was converted to right-hand drive and bodied by Custom Coaches in 2008–2009. It is now being operated by Path Transit, who is one of three contractors that operates buses under the Transperth brand name in Perth, Western Australia.