"Black Friday, 80% off", screams one online advert. "50% off all Black Friday sales", says another. And the same goes for newspapers, TV, radio stations as well as shop display windows.

Tomorrow is Black Friday and long queues will be snaking out of many retail outlets as shoppers jostle to get to the front to find heavily discounted products before they run out.

But it is easy for Black Friday to turn into Red Friday - the day your finances go from the black to the red - if you spend your last cent so as not to miss out on this annual shopping splurge.

Retailers hold this annual sale at this time of the year because they want you to spend your hard-earned annual bonuses if you are one of the lucky employees who receive one.

Although retailers are obviously the biggest beneficiaries, reporting brisk business during this period, the banks will be smiling too.

One banker reported that Black Friday is now the day where the largest volume of credit and debit card transactions are registered in a single day in South Africa.

Checkers was the first to introduce Black Friday sales to South Africa in 2014, and some retailers now reportedly collect more on Black Friday than they do in the days before Christmas, which had been the busiest and most profitable period of the year.

However, not all retailers look forward to this day.

Anwer Ahmed, who runs Moochie's boutique at St Peter's Square Mall in Observatory, Cape Town, said Black Friday tends to benefit the "big boys" in the retail industry.

Smaller operators risk losing out during this period if they don't play their cards well, he said.

"You will find that you have had a lot of turnover, but no profit. Last year I made four or five trips to restock. It wasn't profitable for me, but I just had to keep my customers happy."

Ahmed said in the US, where the concept originated, retailers make a profit from sales in the run-up to Thanksgiving, held every fourth Thursday of November.

Black Friday follows Thanksgiving night and offers retailers a way to clear the stock they would have bought for the shopping spree that precedes Thanksgiving.

In South Africa, however, Black Friday is geared more to separating you from bonus payments. Give some thought to how you spend and what you spend it on.

Your bonus could mean many things to you if you use it wisely - it can pay off debt that will cost you much more the longer you take to pay it off, or rather, invest it well for your future needs.