Munich-based BMW said on Friday sales of its core premium brand rose6.1 percent last month to 167,584 cars and sport-utility vehicles, beating its two competitors.
Adding sales of its Mini brand, BMW posted a new record for September in its European home region where closest challenger Audi suffered a 1.6 percent sales drop.
BMW, heading for a 10th straight year as global luxury-sales market leader, has seen its overall advantage over Audi shrink to 20,842 cars after nine months of 2014, compared with 28,836 at the same time a year ago.
The year-to-date gap between BMW and third-placed Mercedes-Benz has shrunk to 124,336 vehicles from 146,946 autos in 2013, due to new model releases.
Mercedes-Benz is enjoying strong demand for a series of redesigned cars, including the E-Class and the flagship S-Class saloon. The Stuttgart-based brand also launched a new C-Class and the GLA offroader in March, paving the way for further improvement in the remainder of the year.
However, the pecking order in the three-way German luxury sales battle is unlikely to change any time soon, research firm IHS Automotive said.
Deliveries of BMW brand cars may jump 23 percent to 2.04 million models by 2019 from an estimated 1.66 million this year, according to IHS. By comparison, sales may rise 16 percent at Audi to 1.91 million and 12 percent at Mercedes to 1.67 million, IHS said.
BMW said on Friday nine-month brand sales were up 9.1 percent to 1.32 million autos. Group deliveries, including the Mini and Rolls-Royce brands, rose 6.5 percent in the first three quarters to a record 1.53 million vehicles.