The Victorian Electoral Commission declared Liberal MP Louise Staley had officially retained her seat of Ripon, in western Victoria, on December 10, edging out Labor's Sarah De Santis in the tightest-fought contest this election.

But Labor's assistant state secretary Kosmos Samaras revealed on Monday evening the party will take court action to challenge the result.

"We will be lodging an appeal with the court of disputed returns," he said.

"The Labor party holds concerns that a formal recount was not performed."

Last week, Mr Samaras said while the ALP was “confident” votes for minor parties had been appropriately scrutineered, it had doubts over votes for Ms Staley and Ms De Santis.

“We were looking for a formal recount from start to finish,” he said.

Before the November 24 election, Ripon was already the Liberals’ most marginal seat, which the party held by just 0.8 per cent.

Winning Ripon will give the Liberal Party four seats held by women in the lower house.

The result is a small win for the Coalition, which suffered a landslide loss against Labor at the state election.