It is believed to be the first time the brand has grabbed number one sales spot for a month.
Mazda’s won’t officially comment on the sales bonanza but dealers are abuzz with the good news.
Federal Chamber of Automotive Industries' January VFACTS sales data due out tomorrow (Wednesday) is expected to show Mazda sold about 3080 3s last month.
That means it has edged out the Holden Commodore and popular Toyota Corolla for number one spot.
Once again small cars are dominating the latest VFACTS figures.
Overall sales started the year 20 per cent down across all leading brands last month.
About 67,000 vehicles were sold last month, down more than 15,000 compared to January 2008's tally of 82,270 vehicles.
Dealers are blaming the poor economic outlook and annual holidays for slow start to the year.
However, despite some individual standouts, most brands had a poor month.
Market leader Toyota was down 25 per cent, Kia 30 per cent and Honda 16 per cent.
Toyota sold about 13,500 new vehicles, down from 17,852 in January 2008.
Holden sold 8500 vehicles, down 15 per cent.
Importer Mazda eclipsed Ford, selling about 6500 cars against Ford's January tally of 6000 vehicles.
Ford sales were down 21 per cent.
Mazda fared better, but sales were still down 8 per cent while Suzuki was down 5.5 per cent.
Korean importer Hyundai sold about 3700 vehicles, down 16 per cent while Volkswagen was down 10 per cent with 2100 sales.
German importer Audi went against the trend.
It sold 1081 vehicles, up 5.5 per cent over January 2008.
January is traditionally a strong retail month.
But many Melbourne dealers are still heavy with 2008 stock and slashing prices ahead of price rises.
Mazda, Suzuki, Nissan and Honda prices rose on January 1.
Buyers of 2009 models will have to pay between $250 and $3500 more, depending on the model.
The car industry is forecasting a 15 per cent fall in sales this year, down from more than 1 million last year to around 850,000.
Top Ten Makes
1. Mazda3 3080
2. Holden Commodore 3000
3. Toyota Corolla 2700
4. Toyota HiLux 2600
5. Toyota Camry 1900
6. Ford Falcon 1800
7. Mitsubishi Lancer 1600
8. Holden Astra 1500
9. Nissan Navara 1150
10. Toyota RAV4 1000