[3] On 9 June, Željezničar and Dino Hasanović negotiated a two-year contract extension lasting until May 2019.

[5] On 13 June, Željezničar announced the loan of 23-year-old Daniel Graovac from Belgium club Mouscron.

[10] On 9 July, Željezničar announced the signing of 29-year-old Josip Projić from Serbian club Napredak Kruševac.

[11] On 23 July, the club appointed 44-year-old Admir Adžem as the new head coach, after releasing Slavko Petrović from his duties.

[16] On 8 August, Željezničar and Kemal Osmanković negotiated a three-year contract extension lasting until 2020.

[17] On 9 August, Željezničar negotiated a three-year contract extension lasting until 2021 with youth players Denis Žerić and Ajdin Mujagić.

[19] On 14 August, Željezničar and Vedran Kjosevski negotiated a three-year contract extension lasting until 2020.

[23] On 25 September, the club announced Aldin Čenan is leaving the position as Director of Sports due to health problems.

[26] On 5 October, the club announced promotion of youth players Filip Dujmović and Semir Dacić to the first team.

[27] On 24 October, Željezničar and Haris Hajdarević negotiated a four-year contract extension lasting until 2021.

[28] On 27 October, the club announced youth players Kemal Mujarić, Eldar Šehić and Dženan Osmanović have signed apprenticeship contracts.

[40] On 21 December, Željezničar announced the signing of 25-year-old Adi Mehremić from Austrian club St.

[41] On 21 December, Željezničar and Irfan Fejzić negotiated a one-and-a-half-year contract extension lasting until 2019.

[44] On 9 January, the club announced an international public call for the submission of bids for the reconstruction of the main pitch of the Grbavica Stadium.

[52] On 22 January, Željezničar announced the signing of 23-year-old Kenan Hadžić from Croatian club Istra 1961.

[53] On 23 January, Željezničar announced the signing of 31-year-old Stojan Vranješ from Polish club Piast Gliwice.