The US economy grew at a rate of 3.5% between July and September, its first expansion in more than a year.
Commentators say the growth was helped by President Barack Obama's $US787 billion stimulus plan. They fear growth will now fall as this comes to an end.
The US economy was also lifted by a federal "cash for clunkers" car subsidy, which ended in August.
The housing market also improved, with spending on housing products up 23.4% - its largest quarterly jump in 23 years.
Analysts say this big leap was sparked by an $US8,000 tax credit for first-time house buyers.
The BBC says says the figures indicate recession has ended, but some economists think there could be further setbacks.
But with unemployment still high, the ongoing recovery is set to be slow.
Total government spending was up 7.9%, as the wider stimulus spending continued to take effect.
Exports were also up strongly, increasing 21.4%, the biggest rise since 1996.