JB Hi-Fi said online sales nearly doubled since the launch of a new website in August last year, accounting for 3.8 per cent of first-half sales, or $4.8m, compared to 2 per cent a year earlier.
Statutory profit after tax was up 37.4% to $151.7 million.
The company lifted its interim dividend 14 cents to 86 cents, fully franked.
Comparable sales in New Zealand increased by 2.4 per cent.
On a brighter note, the company's online sales in New Zealand jumped 90 per cent to $4.8m and are now almost 4pc of total sales.
In addition, sales from The Good Guys totalled $1.1 billion for the six months to the end of December.
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Margins narrowed in the first half of the year too, with group sales up 41 percent, helped by demand for audio devices and drones, double the rate of its underlying net profit. It was another strong result for the JB HI-FI business in Australia, particularly through the important November and December periods. The segment only contributed 3.4% of total sales for the period.
While the overall numbers were down in New Zealand, the company says the launch of a new website in August 2017 significantly stimulated NZ online sales, with growth figures of 89.8% to NZD 4.8 million (3.8% of total sales).
"We continue to reposition the New Zealand business as part of our strategy to improve performance", the retailer said.
The company expects its full-year profit to grow 13-16 percent despite sales rising 22 percent.
"Having owned The Good Guys for over 12 months we are now starting to realise the benefits of scale of the combined group and remain excited by the opportunity to grow of of Australia's leading retail brands", JB Hi-Fi's CEO Richard Murray said.