About six million Australians are expected to take part in Black Friday sales, spending an average of $804 each.

Despite the pull of bargain hunting, consumer advocates such as Choice are telling shoppers to think twice before we buy, with more than 50 per cent of Aussies saying they have regretted a purchase in previous Black Friday sales.

Westpac research says three in 10 Australians admit they are wasting money on duplicate or unused services. It also uncovered that Australians are spending about 20 per cent more on subscriptions than they realise.

Despite such warnings, November foot traffic at retailers is still forecast to be up 4 per cent on last year. It shows the prospect of a good deal is irresistible, even in the grips of a cost-of-living crisis.