The foreign relations between Bosnia and Herzegovina (BiH) and Croatia are bound together by shared history, language, neighboring geography and cultural commonalties.

Croatia agreed to yield the Neum Corridor – 20 kilometres (12 mi) of their 6,400-kilometre coast – to Bosnia in 1991, giving the Bosnian state the second-shortest coastline in the world.

[4][5] Together, Bosnia and Herzegovina and Croatia have signed 111 various treaties deliminating issues ranging from establishment of diplomatic missions to resolving border disputes.

By the end of 1992, however, tensions in Central Bosnia increased, leading to open conflict by early 1993, when Croats established the Croatian Republic of Herzeg-Bosnia.

On 23 February 1994, a ceasefire was reached, and the Washington Agreement was signed on 18 March 1994 leading to the establishment of the Federation of Bosnia and Herzegovina and joint operations against the Serb forces, which helped alter the military balance and bring the Bosnian War to an end.

Croatia was a signatory of the Dayton Peace Agreement, on behalf of itself and of the Croat militias in BiH, thus assuming international obligations.

According to the CIA World Factbook, 7,269 Croatian refugees still live in Bosnia and Herzegovina and the country has 131,600 internally displaced persons.

[9][10] The 2001 agreement on Yugoslavia's succession issues foresaw a follow-up bilateral agreement on the restitution of specific properties of Bosnia and Herzegovina on the territory of Croatia, which include petrol stations, hotels (such as the Hidrogradnja complex in Baška Voda[11]), and assets at the ports of Šibenik and Ploče, for a total worth estimated at 10 billion euros.

Negotiations for a bilateral agreement lasted until 2012, when they were discontinued due to Croatia's unwillingness to agree with Republika Srpska's request for a right to perpetual ownership of the properties.

[16] Sections of the Una River and villages at the base of Mount Plješevica are in Croatia, while some are in Bosnia, which means that there would have to be nine border crossings on a single route.

In 1999, a border agreement between former Croatian President Franjo Tuđman and President of Bosnia and Herzegovina Alija Izetbegović moved the Croatia – Bosnia and Herzegovina border near Neum from the very coast (during SFR Yugoslavia era and confirmed by the Badinter Arbitration Committee) further into the sea waters of the Mali Ston Bay, placing two Croatian islands (Mali and Veliki Škoj, incidentally translated into English as Little and Big Island) under Bosnia-Herzegovina sovereignty.

[20][21] Croatia has opted to build a bridge to the Pelješac peninsula to connect the Croatian mainland with the exclave as part of the A1 motorway Zagreb–Dubrovnik.

[citation needed] Croatia recalled that the foreseen height of the bridge (55 m, 180 ft) will allow the totality of the current Bosnian shipping to use the existing navigational route to transit under the bridge, and that in case any ship taller than 55 meters (180 ft) would need to call on a port in Bosnia and Herzegovina, it could dock instead at the Croatian Ploče port, in line with the 1995 Free Transit agreement.

[citation needed] The construction of the bridge has also been opposed by various political actors in Bosnia and Herzegovina, mostly Bosniak, as they deem it would complicate the country's access to international waters.

[22] Bosnian authorities initially opposed the building of the bridge, originally planned to be only 35 meters (115 feet) high, because it would have made it impossible for large ships to enter the harbor of Neum.

[23] Although Neum harbor is not currently fit for commercial traffic, and most of the trade to and from Bosnia and Herzegovina goes through the Croatian port of Ploče, the Bosnian government declared that a new one might be built in the future, and that the construction of the bridge would compromise this ambition.

Croatia’s conveyed the view that the election of Komsić should never happen again, as it is seen as undermining "the equality of constituent nations" in Bosnia and Herzegovina, between the three main ethnic groups of Bosniaks, Croats, and Serbs.

[29] Since 2018, increased migratory flows has posed challenges at the border between Croatia and Bosnia and Herzegovina, in particular along the region of Una-Sana Canton.

Civil society and international organisations has reported violent collective expulsion (pushbacks) of migrants and asylum seekers back into Bosnia and Herzegovina.

Bosnia and Herzegovina objected to Croatia's plans to build a radioactive waste disposal site across the border in Trgovska Gora, Dvor (former Cerkezovac barracks) in 2021.

[31] The Croatian government has raised concerns about the cross-border impact of pollution from the fuel refinery in Brod (BiH), owned by Russian state-owned company Zarubezhneft.

[33] As Bosnia and Herzegovina and Croatia each share the largest part of their border with the other (932 kilometers or 579 miles), they have participated in numerous joint ventures aimed at providing a regional economic uplift.

Bosnian Croat politician Dragan Čović had been charged with abuse of power and authority during the privatization of Eronet in 1999, but was acquitted by the FBiH Supreme Court in April 2013.