The biggest mistake you're making when you order groceries online

How do you feel about grocery shopping? Do you see it as being a fun expedition, or is it more of a major time-sucking hassle? If you fall into the latter camp, chances are you've considered ordering groceries online. Sure, it's going to be a bit more expensive, what with delivery fees and tips — and let's not forget the price markups. (Of all the major grocery delivery services, only Walmart claims to offer delivery prices that are the same as the ones you'd find on store shelves.) Still, if online grocery shopping can fit into your budget, there's no denying that the service is super convenient and can save you a ton of time and effort.

Before you place your next order, though, there's one thing you really need to be aware of to make sure you get only those items you actually want instead of finding any surprises in your shopping bag: the substitutions policy.

Don't forget to check the substitutions policy when you order groceries online

If you're unaware that grocery delivery services have policies in place to address any out-of-stock items, you may be in for a shock. Many default to substituting any items they think are the best replacements for the ones you ordered, and, as Super Healthy Kids points out, there may not be an upcharge if they have to switch a brand-name item for store-brand, or two 8-ounce items for a pound. That's all well and good if you truly don't mind having another brand — canned tomatoes are canned tomatoes, after all. 

If, on the other hand, you order Doritos and get Tostitos, you may not be too pleased. Or perhaps you want Lemon LaCroix, and they send you Pamplemousse instead — again, not quite what you had in mind. It may be that there's a particular brand or variety that you really do need — as the gluten-sensitive, those allergic to tree nuts, or anyone else dealing with special dietary requirements knows, not just any substitute item is going to work.

Your best option in order to make sure you get everything you need and nothing that's going to make you say "yuck!" is to be really specific in your ordering. My Recipes relates that most services let you select allowed replacements on an item-by-item basis, or even to indicate no substitution in cases where you need a specific item and no other will do.