For every £1 spent in store customers will be entered into a daily draw. Shoppers must keep their receipt and check the numbers online after 8am the next day to find out if they have won.
Every Morrisons store will give away three £100 cash prizes every day until 30 October.
Morrisons says the £2m giveaway is designed to help customers in the run up to Christmas and claims it is the “biggest supermarket cash giveaway ever”.
It has also partnered with The Mirror, which is offering readers the chance to win £10,000 every day for ten days by collecting coupons from the paper alongside Morrisons receipts.
It is the latest in a number of initiatives that supermarkets have launched to tempt shoppers through the doors.
Separately, Morrisons launched a TV ad campaign promoting its recently launched M Kitchen own label range this weekend (15 October).
The ad follows the opening of a pop-up restaurant in London last week staffed by five leading chefs including Aldo Zilli, to show that its new ready meals range provides restaurant quality food at low prices.