The supermarket giant submitted a late bid over the weekend, trumping one from forecourt empire EG Group.
EG, part-owned by the billionaire Issa brothers – who also own Asda – were favourites to snap up McColl’s with an offer on Friday.
But Morrisons came forward with an improved deal and is buying all 1,160 McColl’s stores.
This includes 270 currently run as Morrisons Daily.
All McColl’s staff will transfer over and banks owed £160million will get their money immediately.
The supermarket will also take on responsibility for the 2,000-plus members of its two pension schemes.
The purchase followed McColl’s being placed into administration, with PwC appointed yesterday to oversee the sale.
David Potts, Morrisons chief executive, said: “We believe this is a good outcome for McColl’s and all its stakeholders.
“This transaction offers stability and continuity for the McColl’s business and, in particular, a better outcome for its colleagues and pensioners.”
Rob Lewis, joint administrator and partner at PwC, said: “The completion of this transaction provides much-needed certainty to McColl’s staff after a period of understandable concern following the group’s challenges over the past months.
“All in all, a really positive outcome.”
Morrisons – owned by private equity firm Clayton, Dubilier & Rice – is the biggest unsecured creditor to McColl’s, being owed £130million.
The convenience store chain had struggled under a heavy debt burden in the pandemic, tough trading conditions of late plus supply chain issues.
Shareholders have seen the value of their investment virtually wiped out over the past year.
The deal is a rare setback for Blackburn brothers Mohsin and Zuber Issa. Along with private equity partners TDR, they bought Asda for £6.8billion last year.