The move is part of integration plans between the two retailers following the grocery giant's £1.4bn takeover of Argos and Habitat owner Home Retail Group last year.
Sainsbury's has committed to opening 250 Argos concessions over three years, with boss Mike Coupe saying every supermarket in the country will eventually have either a store-in-store or a click-and-collect point.
Argos also said it plans to transform 60 stand-alone Argos stores to a digital format.
The move comes as the big four grocer looks to bolster the number of mini-Habitat stores in its supermarkets from seven to 17 by the end of the financial year.
Argos chief John Rogers said: "The opening of our fiftieth Argos Digital store just seven months after we acquired the company shows we are moving ahead at pace with our strategy.
"Our decision to transform 60 Argos stores by March next year moves our strategy on further."
The takeover of Home Retail aims to deliver cost savings and give the firm greater firepower to take on the likes of Amazon.
In an update last month, Sainsbury's said trading remained "very competitive" and warned over continuing price pressures from the weak pound as it saw supermarket sales slip back into reverse.
It posted a 0.5 per cent fall in like-for-like supermarket sales, excluding fuel, in its fourth quarter to March 11, down from a rise of 0.1 per cent in the previous three months.