Toyota Australia has brought forward substantial price cuts stemming from planned tax reductions on vehicles imported from Japan.

Sales and marketing chief Tony Cramb said the company cut its prices from 1 January - at least two weeks ahead of the official reductions in vehicle import duty negotiated as part of the Australia-Japan free-trade agreement.

"Toyota decided to act from the start of 2015 by lowering prices for customers immediately, rather than waiting for the duty reductions that will start flowing from 15 January," Cramb said.

"Prices came down from the start of the year by around A$800 (US$649) on our most affordable Yaris range while some of our more expensive models have attracted reductions as high as A$7,630," he said.

"Based on 2014 sales figures, this move is expected to result in lower prices for well over 100,000 Toyota vehicles in the coming year - or more than half Toyota's annual sales in Australia."

The landmark deal, known officially as the Japan-Australia Economic Partnership Agreement, will ultimately slash the duty paid on vehicles imported into Australia from 5% to zero.

Toyota's biggest-selling models affected by the changes are the LandCruiser family - 200 and 70 Series, Prado and FJ Cruiser - RAV4, Corolla hatchback and Yaris.

The Camry and Aurion are not included because they are built locally. Australia already has free-trade agreements with Thailand (source of HiLux trucks and the Corolla sedan) and the US (Kluger).

Cramb said cutting prices in advance of the duty reductions was a clear signal of Toyota's determination to improve all aspects of its business in the interests of customers.