[1] Garry Fleming lead the list, departing after 179 appearances for the club, he was joined by Tom Lang, Mark Docherty and Donald McCallum.
[12] Jamie Ewings was announced as the club's new goalkeeper coach on 9 June,[13] before Andy Dowie became their first signing of the summer – joining from Queen of the South.
[18] On 26 June there were further boardroom changes, as Ian Wilson (one of the main members of Brabco, and drivers behind the new stadium move) resigned from the board, in order to concentrate on the holding company's other interests.
[21] June ended with the club revealing their new Joma home kit, which was a modern take on their traditional white, black and gold colours.
[23] Winger Chris Johnston became the club's third summer arrival from Raith Rovers, after Mark Stewart and Craig Barr, joining on 7 July.
[27] Dumbarton ended their pre-season campaign unbeaten, after goals from Calum Gallagher and Mark Stewart gave them a 2-1 victory over local rivals Clydebank on 15 July.
[30] Following injuries to Grant Gallagher and Stuart Carswell midfielder Kyle Hutton joined the squad from St Mirren on 21 July, having previously worked with Ian Durrant at Rangers.
August began with Stevie Aitken securing the signing of Celtic U20s captain Sam Wardrop on a season long development loan.
[35] After scoring just once in four league games (two draws, two defeats) Stevie Aitken dipped into the transfer market again on 30 August to sign Ross County striker Greg Morrison, on loan from the Scottish Premiership side until January.
The following week attacker Dimitris Froxylias agreed a contract extension until the end of the season,[44] after impressing with 3 goals and 2 assists in his 8 appearances for the club.
The month ended winless in the league for Sons, with Dundee United taking all three points thanks to two goals from former Dumbarton loanee Sam Stanton.
November began with Sons securing their first away league win of the season, 1-0 against Brechin City thanks to an injury time Willie Dyer own-goal.
Later in the week young midfielder Kyle Prior joined Lowland Football League side BSC Glasgow on loan until the end of the season.
[53] An early Joe Cardle goal consigned the club to their first defeat of 2018 against Dunfermline Athletic, a result that also left them without a home league victory since September.
[57] A day later Dumbarton extended their run in the Scottish Cup with a 3-2 victory against Peterhead at Balmoor Stadium thanks to a double from Calum Gallagher and Iain Russell's first goal for the club since returning.
Despite the cup success however, Dumbarton remained winless (and goal-less) in the league in 2018, as first-half goals from Alan Lithgow and Ryan Hardie consigned them to a 2-0 defeat to Livingston.
Danny Handling's first goal for the club was followed by a stunning, late, Dimitris Froxylias free-kick, as Sons overcame Welsh Premier League Champions The New Saints to reach the final of the Scottish Challenge Cup.
Four days later Brechin were defeated again, this time at Glebe Park, thanks to first league goals for the club from Calum Gallagher and Danny Handling and a Sean Crighton own-goal.
It was heartbreak in the 2018 Scottish Challenge Cup Final however, as Carl Tremarco won the game in injury time for Inverness Caledonian Thistle.
[64] On the park meanwhile a last minute defeat to Greenock Morton left the Sons eight points adrift of eighth placed Falkirk with just four games remaining.
Ninth place was confirmed after two defeats in five days to Inverness Caledonian Thistle, coupled with victory for Falkirk against Champions St Mirren, left the Sons 11 points adrift with just two matches remaining.
[68] In the first-leg of the playoff final Sons defeated League One Arbroath 2-1 thanks to an injury time Craig Barr goal - with the defender only playing after appealing his red card.