The development has been on the cards since delivered wholesaler Palmer & Harvey McLane bought Smile's Somerset-based parent company T&A Symonds last month.
James Lancaster, chairman of Martin McColl, said the addition of the 92-strong Smile store estate would further enhance its position as "the country's leading independent neighbourhood retailer".
The Martin McColl portfolio currently numbers 1,340 stores. Industry insiders believe it could be a matter of weeks before the entire Smile store estate is re-branded to the McColl's facia.
"Given the massive re-branding exercise that Martin McColl underwent last year, I wouldn't be surprised to see the Smile store estate re-branded almost immediately," said one.