Why Milk Comes in Bags in Parts of Canada

In some parts of Canada—like Ontario, Quebec, and the Maritimes—milk comes in plastic bags instead of cartons or jugs. While unusual to outsiders, this packaging dates back to the late 1960s and has practical roots.

The Shift to Plastic Bags
Before 1967, Canadians used glass bottles for milk. When DuPont introduced lighter, cheaper plastic bags, they quickly caught on. Then, in 1970, Canada switched to the metric system. Rather than redesign all the glass containers, milk bags easily adapted to new measurements, making them the ideal choice.

Why Bagged Milk Stuck Around

Eco-Friendly: Uses less plastic than jugs or cartons.
Convenient: Lightweight, easy to store, and sold in packs of three. You snip the corner and pour from a reusable jug.
Freshness: Each bag is sealed, helping milk stay fresh longer.

Though only common in parts of Canada (and rarely in the U.S.), bagged milk has become a cultural staple—practical, efficient, and uniquely Canadian.