Although Niki is often described as "low-cost", it provides full service, such as free refreshments, newspapers and baggage. It offers a sandwich or a cold snack, soft drinks, tea and coffee on all short-haul flights as well as on charter routes to Greece, Tunisia and Turkey. On mid-haul charter flights to the Canary Islands and Egypt all passengers are offered a warm snack. Also, gourmet menus from Demel can be ordered before the flight. There is also a buy on board service.
On 9 January 2004, Niki announced cooperation with Air Berlin. In late 2011, Niki merged completely with Air Berlin, sharing operations, booking systems and aircraft. Since 20 March 2012, Niki is an "affiliate member" of Oneworld as a subsidiary company of Air Berlin. Since late 2012, Niki successively repaints their aircraft in the Air Berlin paint scheme, using the Niki logo only at the nose. The new paint scheme will be applied during regular C checks.
In October 2014, Niki announced the cancellation of their flights from Vienna to Copenhagen, Moscow and Frankfurt due to decreasing demand. In exchange, new leisure routes will be started by summer 2015.
During November 2015, Niki along with its parent company announce to terminate their Airbus A319s as the parent announce to spread their A319 out of service. The 10 A319 (4 in Air Berlin, 5 in Niki along EC-LRS in Vueling), Those A319s will be transferred to VietJet Air during 2016 and expected to be completed by 2017 as the group decided to have A320 and A321 instead.