The drop in like-for-like sales for the eight weeks to February 27th is thought to be due to bad weather in the early part of the year and a late spring/summer catalogue launch.
For the full year, Argos sales rose 1.5 per cent to £4.35 billion.
The early decline has not affected Home Retail Group's expectations for the year ahead, though.
Chief exec Terry Duddy said full year pre-tax profits are likely to be around £290 million, slightly ahead of market expectations.
He said: "This is a good outcome to a challenging year and is combined with excellent cash generation."