By mid summer, Audi had exported and sold around 37,000 models to the USA, compared with a total around the 41,000 mark for the UK.
In the UK, Audi sales so far this year are over 7% ahead of this time last year and September will add to the brand's impetus.
"We're predicting 13,500 new car sales this month," an Audi UK spokesman said.
The importer says the UK has been spurred-on by the lowest age profile of any premium car brand in the UK thanks to the image of the TT Coupe.
Audi UK is planning to sell around 78,000 models in the UK this year, about 10% more than the 65,656 units achieved in 2003.