According to Sportitalia, Immobile is on the verge of signing a lengthy new contract that will keep him at the Stadio Olimpico until the age of at least 36.
That would make it a five-year contract with option to extend for a further year after that.
The salary is expected to be around €3.5-4m per season plus performance-related bonuses.
Having travelled widely during his career at Juventus, Genoa, Torino, Borussia Dortmund and Sevilla, Immobile finally found a home at Lazio in 2016.
The 2019-20 campaign was the best of his career, winning the Capocannoniere title, the Golden Shoe award as top scorer in European league competition and equalling Gonzalo Higuain’s all-time record of 36 Serie A goals in a single season.