Since it was a financially poor club, they used to organize dance nights and all the profits made were later used to buy shoes and balls.

The first official match, a friendly, was played at Kovačići, a Sarajevo settlement, on 17 September 1921 against SAŠK Napredak which resulted in a 5–1 defeat.

[4] The club first appeared in European competitions during the 1963 Mitropa Cup, however serious competitions had to wait until the early 1970s when the team finished the 1970–71 Yugoslav First League season in 2nd place, a result which allowed the club to play in the 1971–72 UEFA Cup where they made the quarter-finals on their very first appearance losing to Ferencvárosi in a penalty shootout.

The game between Željezničar and FK Rad scheduled to be played on 5 April 1992 at Stadion Grbavica as part of Round 26 of the 1991–92 Yugoslav First League was abandoned 35 minutes (14:55 p.m. local time) before kick-off due to gunfire around the stadium, a result of the first attack on Sarajevo.

[7][8] Ultimately, the club's final completed match in the Yugoslav Championship was a 6–1 defeat on 29 March 1992 in Belgrade against Partizan.

During the 1997–98 championship, a play-off was held and the final match on 5 June saw two big city rivals playing for the trophy.

In the 89th minute, one ball was intercepted on the left side, and after a couple of passes it came to Željezničar forward Hadis Zubanović who scored a dramatic winner.

Under Amar's command, Željezničar also won the 2000–01 national cup, which completed the double, the first time any club in Bosnia and Herzegovina achieved that, securing also the 2001 Bosnian Supercup.

Sir Bobby Robson's Newcastle United, captained by Alan Shearer, were too strong, winning 5–0 on aggregate when Sanel Jahić received a red card in the 69th minute of the reverse leg at St James' Park.

The game was held at Koševo Stadium in front of 36,000 fans from all over Bosnia and Herzegovina, and to this day is among the best attended games in Bosnian club football history, although short of a match at the same stadium between the Bosnia and Herzegovina national football team's 2–1 friendly win over Italy in November 1996, which was attended by 40,000.

The club, as result of losing to Newcastle United, entered the UEFA Cup first round, but lost to Málaga who were an eventual quarter-finalist.

With the return of Amar Osim in the summer of 2009, Željezničar once more claimed the title in the 2009–10 season, but failed to take the double as they lost in the final of the 2009–10 Bosnian cup to Borac Banja Luka on away goals, while remaining undefeated.

The trophy drought ended in May 2018, as the club won the 2017–18 Bosnian Cup under the guidance of then manager Admir Adžem.

[14] On 31 December 2018, Amar Osim came back for a second time to manager Željezničar, signing a three-and-a-half-year contract with the club.

[15] The 2019–20 Bosnian Premier League season ended abruptly on 1 June 2020 due to the ongoing COVID-19 pandemic in Bosnia and Herzegovina,[16] with Željezničar having to settle with a second spot on table.

The 2020–21 season started strongly winning four opening matches, however their run in the 2020–21 UEFA Europa League was affected due to the pandemic.

The first qualifying round match between Maccabi Haifa, originally scheduled to be played on 27 August 2020 was postponed due to five members from Željezničar's delegation testing positive for COVID-19 and the whole team being put into quarantine by the Israeli authorities.

[18] The team returned to Sarajevo before UEFA made a decision to finally play the match on 9 September at Sammy Ofer Stadium in Haifa.

Željezničar traveled again but lost 1–3 (thus eliminated after revised rules due to the pandemic) after being in quarantine 9 days prior with little to no training and no competitive matches since shock loss at home to Mladost Doboj Kakanj in the 5th round on 21 August of the 2020–21 Bosnian Premier League season.

In the middle of an eight-game winless run in the 2020–21 league season, which had culminated with a home draw against Mladost Doboj Kakanj, Amar Osim was sacked by the club on 11 April 2021.

After World War II, Željezničar played at the "6th April" Stadium in Marijin Dvor (there is a building now on the spot, behind the technical sciences secondary school) until 18 June 1950.

Club staff was tired of all that moving and they decided to build its own stadium in Grbavica neighborhood which just started to be redeveloped and urbanized.

Symbolically, the old railway line passed over the hill behind the stadium, and every time a train went by during a match it would sound its whistle to salute the fans.

In 2016, the wooden stand was reconstructed and slightly expanded in a way that all the wood elements were replaced with anti-slip metal in order to meet the UEFA Stadium requirements.

Before the war capacity of the stadium was more than 20,000 unseated, but now it officially has 13,146 seated places with room for around 4,000 more patrons in standing areas.

Such example is a ćevapi – the national dish – restaurant in Baščaršija, Sarajevo's ood bazaar, called Ćevabdžinica "Željo".

From 1945. to 1992. red five-pointed star stood in place of the ball, and words "Sarajevo", "1921" and others were moved form one part of the crest to another many times.

[24] In popular culture, Stole Anđelović (Stole iz Bora) – a passionate club supporter from Bor, Serbia, is known decades (over 40 years) for traveling 450 km to attend most FK Željezničar Sarajevo home games, and was a long time supporter of Yugoslav national team as well as fan of Ivica Osim.

[25][26] A passionate group of fans from 1921.ba TV upload regular Željezničar league and European match reports as well as interviews with players and staff to online stream media; YouTube.

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