The Argentina international was handed a suspended 21-month sentence after being found guilty in July 2016, alongside his father, of hiding earnings from his image rights in offshore accounts.
Spanish law means that first-time offenders are able to serve their time on probation and avoid jail if their sentence is under two years.
But according to El Mundo in Spain, the rest of this suspended sentence will now be scrapped, with Messi paying an increased fine to chalk off the remaining months of his sentence.
They claim the striker will pay €252,000 (£221,202) and his father Jorge will shell out €180,000 (£158,008).
This follows a similar payment made by his Nou Camp team-mate Javier Mascherano in January 2016.
What the payment has done is remove the unlikely possibility that Messi will be forced to spend any time behind bars.
Messi, who turns 30 on Saturday, is currently locked in talks over a new contract with the Catalan side as he gets set to enter the final year of his existing deal.
He netted 54 goals in 52 games last season as the club finished runners-up to bitter rivals Real Madrid in La Liga.