Online retail giant Amazon racked up impressive first quarter revenue and profit growth, and said today it has – so far – not been affected by an economic slowdown in the US.

Q1 profit was up 30 per cent on a healthy 37 per cent climb in revenue, buoyed by increased customer purchases through the firm’s free-shipping schemes.

It pulled in $4.13bn in the first quarter ended 31 March 2008 from net sales, compared with $3.02bn in the same period a year ago.

Seattle-based Amazon reported net income of $143m, or 32 cents a share, from the year ago quarter.

The firm also raised its sales expectations for the year with a forecast for its 2008 sales to reel in between $19.1bn to $20bn, an increase of 29 to 35 per cent from 2007.

However, Amazon added that its operating profit would remain flat, and partly accredited the increased costs incurred from its acquisition of Audible.com earlier this year.

Amazon’s positive results benefited from a number of factors including its Amazon Prime discount shipping program, favourable foreign exchange rates that make overseas sales appear more valuable in dollar terms, and an increase in sales from third party retailers who sell on the website.

Amazon shares closed up 1.8 per cent to $81 on Wall Street following the company's Q1 report. ®