[3] Its purpose is to provide passenger and freight service between participating countries and improve rail connections between Central and Northern Europe, specifically the area southeast of the Baltic Sea.

[6] In 2020, a private consortium claimed that it could open an undersea railway tunnel between Tallinn and Helsinki by mid-2026,[7] but this project has been put on hold indefinitely.

Rail Baltica includes plans for three multimodal freight terminals located in Muuga Harbour (Estonia), Salaspils (Latvia), and Kaunas (Lithuania).

[10] At the end of April 2021, governments of Estonia and Finland signed a memorandum of understanding committing themselves to cooperation in the area of transport.

[16] In addition, Rail Baltica Global Project's cost-benefit analysis was delivered by Ernst & Young and Atkins International experts, based on the European Union's CBA guidelines.

[5] In August 2016, the spatial planning for the entire Rail Baltica railway line was approved in Latvia by the decision of the Latvian Government.

The route for the section from Kaunas to the border with Poland, known as Rail Baltica I, is subject to the results of an Upgrade Feasibility Study.

With Estonia's decision, the spatial territorial planning and preliminary technical design of the Rail Baltica railway in the Baltic states was finalised.

On 20 March 2018, the first Rail Baltica construction design and supervision contract—for Rail Baltica's Riga International Airport railway station, related infrastructure, and viaduct—was signed by Eiropas Dzelzceļa līnijas SIA and PROSIV, the winner of the open international tender and a partnership of suppliers from three countries: Prodex (Slovakia), Sintagma (Italy), and Vektors T (Latvia).

Also, detailed technical design contracts were signed for the following sections: Tallinn–Rapla and Pärnu–Rapla in Estonia, Kaunas–Ramygala and Ramygala–Latvian/Lithuanian border in Lithuania, and Vangaži–Salaspils–Misa and the main line through Riga in Latvia.

[22] On the 3rd of February 2021, the project implementer of Riga Airport Station was also chosen; construction began in May 2021 and is ongoing as of July 2023[update].

[24] The Russian invasion of Ukraine has raised the importance of this European project, because of the connectivity across Europe that it will create, for civilian and military travel.

[28] All construction carried out by the implementing bodies is done under the supervision of RB Rail AS and is based on common procurement principles, rules, and contract templates.

Moreover, the preparation of environmental impact assessments, spatial planning, and some preliminary designs has provided better investment estimations for the project.

[5] Thus, in April 2017, the overall cost of the Rail Baltica Global Project implementation in all three countries—including the construction of the Kaunas–Vilnius section—was estimated to be €5.8 billion, according to a cost-benefit study carried out by Ernst & Young.

[35] In addition, several immeasurable (mostly catalytic) benefits would be created through regional integration, such as tourism development, new business creation, increased attractiveness to FDI, access to new export markets, technological transfer, and innovation.

This substantial funding, combined with national co-financing from the three Baltic States, will exceed 1.1 billion euros, enabling necessary activities for further high-speed infrastructure development.

[41] During the planning of the location of the project route in the Baltic States, a conceptual agreement among the three countries was reached that the railway should be as straight as possible, as this provides the highest benefits at the lowest cost.

For the remainder of the route to Tallinn, two different options were considered: The Šiauliai–Latvian border rail section (using broad gauge) was newly built and scheduled to be finished in 2015[needs update] with an estimated cost of €270 million.

[46] For the Kaunas (Jiesia)–Lithuanian/Polish border section, a 78.1 km route named "alternative 6A" was approved in May 2022 by the Lithuanian Ministry of Transport and Communications, taking into account the opinion of the majority of the local residents.

[49] On 29 February 2024, construction on the Rail Baltica Riga Central Railway Station reached the rooftop, which was celebrated with a ceremony according to Latvian tradition.

[55] Criticism started after the feasibility study published by AECOM in 2011, with the government of Lithuania keen to include a link to Vilnius.

[60] In 2017, two Estonian environmental groups claimed that the lack of public participation on the decision made by Baltic governments and building of a new line, rather than upgrading the existing network, is in conflict with the Aarhus Convention.

[61] In 2016 and 2017, three open letters were composed in Estonia which called on the Estonian government and parliament to stop the project in its planned form.

[62][63][64] The main arguments in these letters were that the new track as a greenfield project will cause too much damage to nature and does not essentially improve travel possibilities.

On 8 June 2017, Priit Humal, Karli Lambot, Illimar Paul, and Raul Vibo, experts on logistics and engineering, published a critical analysis of the Rail Baltica cost-benefit analysis made by Ernst & Young, claiming that €4.1 billion of the stated socio-economic benefits are faulty and therefore the Rail Baltica project was neither feasible nor eligible for EU financing.

[66] The authors of the first study claimed that the issues raised in their previous analysis were not adequately addressed in the official replies and that therefore Rail Baltica will be detrimental to society.