Oslo OSL to Tallinn TLL flight with Norwegian Air

SAS, or Scandinavian Airlines, is the national airline of Denmark, Norway, and Sweden, headquartered in Solna, Sweden. Founded in 1946, it emerged from a merger of the three countries' national carriers to handle transatlantic operations. SAS operates extensive regional services within Scandinavia and Europe, as well as international flights to Asia and North America, with primary hubs in Copenhagen, Stockholm, and Oslo. As of July 2024, SAS, including its subsidiaries SAS Link and SAS Connect, operates a fleet of 133 aircraft to 130 destinations. SAS joined SkyTeam on September 1, 2024, after leaving Star Alliance.

Norwegian Air International (NAI) was an Irish airline and a fully integrated subsidiary of Norwegian Air Shuttle, operating under its corporate identity. Headquartered at Dublin Airport, NAI operated flights to destinations across Europe and the Middle East from various European bases. Between 2017 and 2019, it also offered services from Europe to the United States and Canada. NAI received its operating license and air operator's certificate from Ireland in February 2014, allowing it to leverage European Union airline freedoms. By April 2021, its aircraft and operations were gradually transferred to its Swedish sister airline, Norwegian Air Sweden, and its parent company.

Finnair is the flag carrier and largest airline of Finland, with its main hub at Helsinki Airport. Founded in 1923 as Aero O/Y, it is one of the oldest continuously operating airlines in the world. Finnair is a member of the Oneworld airline alliance and is majority-owned by the Finnish government. The airline specializes in connecting Europe, North America, and Asia via its Helsinki hub, operating flights to over 80 destinations in more than 35 countries. Finnair is known for its focus on sustainability and has a modern, mostly Airbus fleet.

AirBaltic is the flag carrier of Latvia and a leading hybrid airline in the Baltics, combining aspects of traditional network and low-cost carriers. Founded in 1995, it operates a modern fleet of Airbus A220-300 aircraft, connecting the Baltics from hubs in Riga, Tallinn, Vilnius, and Tampere to over 70 destinations across Europe, the Middle East, North Africa, and the Caucasus. The company is majority-owned by the Latvian state. AirBaltic is recognized for its commitment to passenger experience, having received awards for cabin service and being among the world's safest airlines. In a pioneering move, AirBaltic became the first European airline to offer free high-speed SpaceX Starlink internet on its flights in February 2025.

CityJet is an Irish regional airline headquartered in Dublin, Ireland. Founded in 1992, it began operations in 1994, initially flying between Dublin and London City Airport under a franchise agreement with Virgin Atlantic. CityJet transitioned its business model in 2018, ceasing its own-brand scheduled services to focus on wet leasing aircraft to other European airlines. This means CityJet provides aircraft and crew to operate flights on behalf of other carriers. As of 2023, CityJet operates a fleet of Bombardier CRJ900 and CRJ1000 aircraft, primarily for airlines like Scandinavian Airlines (SAS), Lufthansa, and Brussels Airlines. In 2023, CityJet merged with Air Nostrum, forming the Strategic Alliance of Regional Airlines (SARA).

A regional jet (RJ) is a jet-powered regional airliner typically designed to carry fewer than 100 passengers on short-haul flights. These aircraft are often used by regional airlines, which may operate independently or as subsidiaries contracted by larger carriers, to connect smaller markets to major airline hubs. Key manufacturers of regional jets include Embraer and Bombardier, with Embraer's E-Jet family being particularly popular. Regional jets play a crucial role in providing air service to communities that may not have sufficient demand for larger aircraft, facilitating connections within a country or a specific area of a continent.