Shopping online can incredibly convenient, but should you do it for basic school supplies? That depends on what’s more important to you: time or money.

According to a new study from customer service rating firm StellaService, consumers will cough up less cash overall by going the brick-and-mortar route, but the shopping itself will take a lot longer.

Buying a list of 13 basic school supply items — like erasers, markers, paper, and glue sticks — takes about 10 minutes online, compared to 30 minutes in a physical store (plus travel time).

But people willing to venture out in person will save some serious money: they paid $31, compared to the $53 online shoppers shelled out. Shipping fees were responsible for about $10 of that differential, but even the per-item costs online were higher.

Why? It’s all about convenience. People in a hurry to get their shopping done typically don’t mind paying more to do it. What’s more, physical stores are often willing to lose money on cheaper things like school supplies to get people in the door — where they’ll hopefully buy additional items they didn’t even know they wanted.

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