Argos has been trying to revive its fortunes will a digital overhaul of stores and initiatives such as same-day delivery.
Sainsbury's, which already has Argos concessions in some stores, said the deal was "the right thing for the business" and "financially compelling".
The offer now faces a shareholder vote and regulatory scrutiny, but should it go through, will see Home Retail investors receive 55p per share in cash, along with 0.321 new Sainsbury’s shares.
Home Retail shareholders would then own 12% of the total group.