In an environment marked by high inflation and low consumer confidence, the projection corresponds to a nominal increase of 5.8%.
This forecast marks a decline from the 8% growth projected by the association at the beginning of this year.
On a price adjusted basis, online sales will increase by around 2% this year, the HDE added.
"High inflation continues to leave clear traces in the retail sector. This also applies to online retail, which is feeling the effects of consumers' reluctance to buy," said HDE deputy chief executive, Stephan Tromp.
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Impact On Sales Channels
The war has affected all retail sales channels equally, according to the HDE.
During the pandemic online sales grew by more than €25 billion overall during the pandemic years.
Online retail experienced a slight loss in sales for the first time in 2022, with a nominal decline of 2.5% or €2.2 billion.
However, compared to the online sales in 2019 - before the special stimulus for the coronavirus pandemic - the increase was 43%.
The online share of sales of food and drugstore products remained at 4.3%.
In the fashion and accessories and CE/electrical sectors, the online share of the respective total market remained high at over 40%, the HDE noted.