The AIM-listed firm said UK instructions leapt 121% year-on-year in the 19 weeks to September 14, including 3,156 signing up to sell their homes in the month of August.
The company, which is backed by fund manager Neil Woodford and a group of prominent investors, said it had strengthened market share to 65% at the start of September.
Its Australian business, launched at the end of August, was also beginning to bear fruit, with its first two weeks of trading showing valuations "substantially ahead" of its UK business at the same point in its development.
It said it had seen "little discernible impact" from Britain's vote to leave the European Union.
Chief executive Michael Bruce said he was confident the success of its UK business could be replicated in Australia, he said: "Our technology, marketing expertise and strong culture, coupled with our low fixed cost business model makes us best placed to win in this market."
Shares were up more than 4% following the trading update, which came ahead of Thursday's annual general meeting (AGM).
Purplebricks said the UK business was on course to become profitable within this financial year and would meet the board's full-year expectations.
It is also on track to meet its target of recruiting 360 local property experts (LPEs) - the description used for its estate agents - by April next year.
Michael Bruce of Purple Bricks won BQ's Emerging Entrepreneur West Midlands back in February, and will appear at MADE festival in October where the overall winner of Emerging Entrepreneur 2016 will be announced.
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