The bonus, which will be paid at the end of this month, amounts to an average of 1,371 euros ($1,648), or about 6% of annual reference average salary, national metal mechanic unions said in a statement.
That exceeds a 1,350 euro average bonus paid last year and a 1,250 euro payment made two years ago by Stellantis predecessor Fiat Chrysler (FCA).
Stellantis, the world’s fourth automaker, was created last month as FCA and French rival PSA completed their merger process.
Gianluca Ficco, of UILM union, said some 54,000 workers of former FCA in Italy will receive the bonus.
He said the increased bonus showed that the automaker and the unions had signed a good national agreement.
“It also shows the workers’ effort to keep efficiency high at Italian plants, despite all the problems caused by the COVID-19 pandemic,” he said.
Italian employees of former PSA, a few hundred people mostly with sales jobs and hired with a different contract, are not entitled to the bonus.
FCA froze its production in Italy for almost two months last spring, as the country was hit by one of the world’s toughest lockdowns following the coronavirus outbreak.
Stellantis has pledged not to close any plants or cut jobs following the FCA-PSA merger and Chief executive Carlos Tavares has said that all brands and all plants would be given a chance.
($1 = 0.8318 euros) Reporting by Giulio Piovaccari, editing by Jane Merriman