Ditching these bad habits will save you time, money, and sanity on your next grocery run.

Grocery shopping is so fundamental to all of our lives that it might seem incomprehensible that we may be doing any part of it wrong. And wrong is probably not the right word, but there is no question that almost all of us could be shopping smarter, more efficiently, and avoiding some common mistakes. So, here are the five biggest shopping errors to avoid on your next grocery run.

Mistake #1: Shopping Blind

Making a grocery list might seem like adding one more thing to your endless to-dos, but a list will save you both time and money. Here’s how: If you hit the store without a list, you are more likely to go up and down almost every aisle, assuming that when you see the item you need, it will spark your memory and you’ll be simply grab it. This slow meander through the store is great if you are not under a time constraint, and if you like to have your shopping be an experience rather than just a task.

But chances are that not only will you likely forget at least one item you need, potentially necessitating another shopping trip, but also that you will do significantly more impulse buying along the way. Jot down your list, if possible, in groupings that are likely to be found together or near each other in the store (produce/household supplies/canned goods/dairy/etc.) and stick to the list when you shop.

Mistake #2: Shopping Hungry

This might seem like some sort of diet advice, but actually it is more of a financial concern. Sure, you might make slightly less healthy choices if you are starving when you hit the store (we have all had a Cheetos related snaccident from time to time). But more than this, you are likely to overbuy generally when you are hungry, even if the choices you are making are healthy ones.

And strangely, you will always lose more money on healthy overstock than junk food. Why? Because junk food is more often shelf-stable, full of preservatives, and can stick around your house for a long time. But fresh produce, dairy products, and raw meats have limited shelf life. And when we overbuy, we are more likely to end up throwing away spoiled food. Even if it is just a handful of nuts—or one of our favorite grab-and-go packaged snack options—try to eat something before you hit the store. If you didn’t have time or remember to grab something? A quick fix is right at the checkout. Buy a granola or protein bar at the front when you first arrive, and eat it while you shop, a small initial investment to prevent overspending in the long run.

Mistake #3: Always Buying Large

There is no question that larger formats of things have a smaller per-piece or per-ounce cost than their mini versions, and stores are only too willing to show you those differences right on the pricing labels. It can feel almost wasteful to buy the smaller version at $1 per ounce if the big one is $.59 an ounce. But you will only really enjoy those savings if the product is something you use a lot of and will fully consume before the expiration date. Even pantry items and condiments that have a long life eventually deteriorate, so be smart about the initial purchase.

If your family goes through Ranch dressing like it is a beverage, hit the big box store and grab a keg of it. But if you are trying out a new recipe that calls for an exotic ingredient that you have never used before, buy only the smallest amount that serves the needs of that recipe when you make your first buy. If you fall in love with it, you can buy the big one when you run out! The same is true when testing a brand replacement for a household staple. Whether it is a different paper towel, dishwashing pod, or countertop spray, if the store is out of your usual brand, or there is a new one you want to try, get the smallest one first in case you hate it. There is nothing worse than having 20 rolls of toilet paper that your spouse loathes.

Mistake #4: Buying Out of Season

The produce section of your store is always stocked, and that strawberry display is full year-round. We won’t get into the delicious factor here. If you don’t mind a wooly, hard, bland strawberry, that is your business, but the financial factor is significant. Out of season fruit and vegetables can be anywhere from 20 - 400% higher than when they are in season, depending on how far they have traveled to get to you. But sometimes when things are available all the time, we can blindly add them to our carts without checking prices, and ultimately you will feel that squeeze at the checkout.

Mistake #5: Ignoring Store Brands

Many people assume that the store brand means generic or lesser quality than national brands whose names you recognize. But this is not always the case. Often the product inside is coming from the same place! Costco Kirkland brand vodka is the exact same vodka as super premium Grey Goose—same distillery!—you just aren’t paying for the fancy Grey Goose marketing and packaging. Store brands can often be a great way to save, especially on staples, and tend to be the first items to go on sale, so give them a try before brushing them off. You might discover some great savings.