It was a narrow victory over the Scottish Conservative’s Sarah Patrick, who came just a few votes away from joining her father, Councillor John Patrick, as a representative of the ward.
In the end, however, Ms Russell took 1691 votes, while Ms Patrick got 1676.
And that means the SNP now have two members representing Falkirk South as Ms Russell joins Councillor Lorna Binnie.
It was a painful night for Labour, who failed to hold on to the seat, following the surprise resignation of Pat Reid in August.
The Scottish Labour party candidate, James Marshall, got 679 votes, while the Scottish Green Party’s Stuart Duffin won 267 votes.
There were 4313 valid papers and 51 rejected papers.
During the count, the atmosphere in Falkirk High School was subdued as Covid regulations meant a limit to the number of observers allowed in.
But outside, a small crowd of supporters braved the cold and waited until after midnight to give Ms Russell a huge cheer when she went out to thank them for all their efforts.
A delighted Ms Russell said she couldn’t wait to get started.
She told the Local Democracy Reporting Service: “I’m really excited – it’s been hard fought but I have had an amazing team behind me.
“The result showed that the SNP administration is looking after the people of Falkirk South.
“The Tories and Labour coming together in recent weeks has almost destroyed the regeneration of Falkirk town centre.
“I think they have to step back now and look at what’s happened.”
With her induction taking place today (Friday) she says she just wants to “get stuck in!”
She added: “I spent the past eight weeks speaking to people and hearing their concerns and finding out what they want.
“I’m now looking forward to working with my ward partner, Lorna Binnie, for the people of Falkirk South.”
Council leader Cecil Meiklejohn warmly welcomed her new colleague to the SNP group, which will be strengthened although still a minority administration.
She said: “I am just absolutely delighted to have Emma join our SNP administration.
“She will strengthen the team and she’ll bring with her knowledge, skills and experience that will be of benefit to Falkirk Council and the citizens of Falkirk South.”
While the final result did not go in their favour, the Conservatives said they were pleased with the result which saw a 6.8 per cent increase in their vote.
Their spokesperson, Neil Benny, said after the result was announced: “This puts us in poll position to be the real alternative to the SNP at the elections next May.
“The people of Falkirk have a choice between a failing SNP administration or change and growth under the Scottish Conservatives.
“Sarah has been a fantastic candidate and she has shown what a real alternative in Falkirk South would look like.
He added: “The Labour Party is a busted flush in Falkirk!”
Ms Russell will serve until the Scottish council elections which take place next May.