Black Friday and Cyber Monday sales are expected to be bigger than ever this year: 13.8 million Australian consumers are forecast to spend about $5 billion over the four-day spendathon, up from an estimated $3.9 billion in 2019.

The promotion, which started in the US in the 1950s and has spread around the world with the growth in online shopping, is now firmly established in the Australian retail calendar and its growth has contributed to the fact that retail sales in November now exceed those in December.