Stop buying groceries when you are hungry. That is rule one, and it is the cheapest change you will ever make. My grocery bill dropped about 15 percent the month I started eating before I shopped.

No coupons required. Here is the whole system.

The rules I shop by

1. Eat before you go. Hunger makes you buy food you will not cook.
2. Make a list and stick to it. A list is a contract with yourself.
3. Shop the perimeter. Produce, meat, dairy, bread. The aisles are where the processed markup lives.
4. Compare price per unit, not package price. The big box is not always cheaper.

Buy what you will actually use

The biggest waste in my kitchen was produce I bought with hope. A bunch of herbs for one recipe, half of it brown by Tuesday. Plan meals around what is on sale and buy loose produce so you get exactly what you need.

Store brands are not a sacrifice

I switched my staples, flour, sugar, canned tomatoes, pasta, to store brand versions. Same ingredients, 20 to 30 percent less. For most pantry basics, the name brand is paying for the label.

The frozen aisle is your friend

Frozen vegetables and fruit are picked and frozen at peak ripeness, and they are cheaper than fresh most of the year. Frozen berries go into my smoothies and cost half what fresh ones do. Nobody can tell the difference in a smoothie.

One more trick

Do your big shop once a week and fill in with small trips only when you run out of essentials. Every trip to the store is a chance to overspend. Fewer trips, fewer impulse buys, more money left.