JB Hi-Fi has bumped up its full-year profit guidance following a surge in sales since March as customers forced to work from home boosted demand for home appliances and technology products.

The electronics and appliances retailer on Thursday said second-half comparable sales at its JB Hi-Fi Australia stores were up 20 per cent compared to 4.4 per cent in the first-half.

Sales at subsidiary chain The Good Guys, which focuses on electrical and home appliances, were up 23.5 per cent from 0.6 per cent in the first half.

This comes on the back of an 11.3 per cent increase in comparable sales in Australia in the March quarter.

“The group has seen strong sales growth in the second half of FY20 in JB HI-FI Australia and The Good Guys as customers spend more time working, learning and enjoying entertainment at home,” the company said in a statement to the ASX.

The elevated sales growth, combined with disciplined cost control, has more than offset the additional operating costs associated with ensuring safety for staff and customers during COVID-19, it said.

It did feel a negative impact at its 14-store New Zealand network which was closed in March and April due to restrictions there.

Given the impact of the temporary closure, the group is reviewing the carrying value of its New Zealand business and will take a non-cash impairment of $25 million in its full year accounts.

JB Hi-Fi said all New Zealand stores have resumed full trading and initial sales performance since reopening has been solid.

The retailer also reinstated a revised FY20 sales and earnings guidance after withdrawing it in March amid the uncertainty arising from COVID-19.

The group now expects full-year sales to be $7.86 billion, up from $7.1 billion last financial year, while net profit is expected to be 20 to 22 per cent higher, in the range of $300 million to $305 million.