Italy's new-car registrations rose 8.1 percent to 166,956 units in September, according to figures published by the transport ministry on Monday.
That sales volume was the country's best result for the month since 2009. The strong gain came despite September having one less working day than 2016.
Italy is now in position to have its fourth consecutive year of sales growth, car importers association UNRAE said after the figures were released.
Market leader Fiat Chrysler Automobiles saw sales rise 5.2 percent, helped by a 44 percent jump in Jeep volume, while core brand Fiat was up 2.7 percent.
Volkswagen Group posted a 14 percent increase, helped by a 60 percent jump at Spanish unit Seat and a 23 percent gain by premium brand Audi. VW brand sales were up 7.1 percent.
Renault Group sales rose 22 percent, boosted by a 25 percent rise at the core Renault brand, while French rival PSA Group's registrations increased 15 percent largely because of a 20 percent gain by Citroen.
Opel's sales were almost flat, rising just 0.9 percent, while Ford's volume declined 1 percent.
Among premium automakers, Daimler's Mercedes-Benz Cars unit was up 2.4 percent. The automaker got a 7.1 percent increase from the Mercedes brand but its small car unit, Smart, fell 7.5 percent. Registrations at rival BMW Group grew 1.9 percent, with a 3.4 percent rise at Mini, which outpaced a 1.2 percent jump at the BMW brand.
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Among Asian carmakers, Nissan was the big winner with a 57 percent jump in sales last month, helped by demand for its new Micra and popular Qashqai compact crossover.
Toyota registrations rose 7.7 percent, while Hyundai posted a 5.1 percent increase in volume. In contrast, Kia's sales fell 10 percent, while registrations at Honda plummeted 19 percent.
According to figures from Dataforce, self-registrations jumped 50 percent and 18 percent by dealers and automakers, respectively, in September.
Federauto, the country's dealer association, expects the country's full-year volume to be about 2 million, in part due to self-registrations, which it says will amount to 15 percent of the total volume.
Italy sales in the first nine months increased 9 percent to 1.53 million.