They were founded in September 1899 by Fred Stoker, who was the club's first secretary before forming a practice as a distinguished physician in London's Harley Street.

The club is most notable for its 1977–78 FA Cup campaign, in which they went all the way to the fifth round, eventually losing to Wrexham in a replay at St James' Park.

The club were then drawn to play away at Wrexham (whose victory over Newcastle United denied Spartans a tie against their North East neighbours) where they drew 1–1.

Blyth would have won the tie but for an unusual sequence when referee Alf Grey ordered a Wrexham corner retaken owing to a technical infringement, enabling Dixie McNeil to score a very late equaliser for the Welsh club.

[1] The replay took place at Newcastle United's St James' Park where, watched by a crowd of 42,167, Blyth eventually went out, losing 2–1, meaning they missed out on a home tie with Arsenal.

Blyth again faced Wrexham and triumphed tie 3–2 on aggregate, having first won 2–1 away in Wales and drawing 1–1 at home in the return fixture.

Since gaining promotion the club has held its own in the Premier division, finishing 6th and 7th in its first two seasons as well as lifting the President's Cup defeating former Conference side Runcorn in the final.

In their first season in the Conference North, Blyth cemented themselves in the top half of the table whilst even enjoying a brief stint in 1st place.

A hard-fought 0–0 draw on the south coast saw Blyth take Bournemouth back to Croft Park, where Ged Dalton put them through to the third round with a last-minute winner.

[7][8] In the third round, Blyth played Premier League opposition competitively for the first time in their history when they welcomed Blackburn Rovers to Croft Park.

In a game again covered live by Setanta Sports, Blyth fell to a 1–0 defeat with the only goal coming via a direct free kick from Chilean player of the year Carlos Villanueva in the 59th minute.

[9][10][11] After two successful campaigns to preserve Conference North status, the 2008–09 season saw the end of Harry Dunn's second spell at Croft Park.

He along with his assistant Gavin Fell made a complete overhaul of the squad that summer, letting popular players such as Robbie Dale leave.

That summer Wade brought in promising youngsters including Rob Nolan and Dean Holmes from North Shields.

In the first qualifying round, Blyth drew 0–0 at Darlington 1883 and won 3–0 at home with a goal from Robbie Dale and a brace from Dan Maguire.

After 90 minutes of play during which it seemed there was going to be a replay at Croft Park, Jarrett Rivers scored an injury time goal to send the Spartans into the fourth qualifying round.

Braces from Dale and Maguire left the fans delighted with a 4–1 win that would take Blyth to the Second Round Proper for the fourteenth time in their history.

Blyth were drawn at home against Birmingham City, which was controversially described by Stephen Turnbull as "a bit of an anti-climax",[22] for him and every Spartans supporter hoped for a Premier League club.

[23] However, Birmingham would go on to score three goals in six minutes to end the North East side's hopes of reaching the fourth round for the second time.

[25] Ten days later, Blyth lost 4–3 again, this time to Northern League side North Shields in the Northumberland Senior Cup Final at St. James's Park.

The club announced on 22 September 2016 that former Ipswich Town striker Alun Armstrong was appointed as manager following Wade's resignation.

In the first one, which lasted from the beginning of 2017 until the dying days of February, the Spartans won all of their twelve games, scoring 44 goals and conceding a mere 11.

[30] The success achieved by the club in the 2016–17 season meant that the Spartans were once again promoted to the National League North, five years after their relegation in 2012.

[31][32] On 1 June 2019, Blyth Spartans announced the appointment of former Newcastle United and Sunderland midfielder Lee Clark as their new manager.

Under Clark, Spartans lost their first four league matches of the season,[34] before picking up a point at Bradford Park Avenue.

[40] On 16 October 2024, chairman Liaquat announced his intentions to sell the club with immediate effect, citing ongoing boycotts and protests as a key factor in his decision.

[42] On 31 October 2024, the club announced that they had been taken over by a newly former Community Interest Company, "Blyth Spartans CIC 2024", led by local businessman Martin Trinder.

[44][45] They continued until 1921 when women's football was banned from its grounds by the FA[46] In 2001 a Blyth Spartans Ladies team was again formed, but despite considerable success closed in 2009.

The team had won the Northumberland Football Association Women's Cup Final in May 2008, scoring 4–2 against Whitley Bay Ladies.

[49] To celebrate Croft Park's centenary Blyth played a Newcastle United side, the team who provided its first opposition.