Competition may be the driving force behind Countdown's decision to drive down costs.

From Monday, the supermarket chain will freeze prices on 500 essential over the winter months in response to the cost of living.

It includes a wide variety of staples - from tinned tomatoes, to butter, sugar, flour and more.

Night 'n Day general manager Matthew Lane told Heather du Plessis-Allan it's likely a result to The Warehouse breaking into the market.

He says it's hard to break into this market due to the major competitors, so The Warehouse is giving a good nudge with the likes of $4 butter and $3 milk.

LISTEN ABOVE