The bulk version of a product doesn't always give you the best bang for your buck. To figure out which size of a given product is really the best value, it helps to look at the unit price. That tells you how much you're paying per ounce or item in a package.
Calculating the unit price isn't always easy, though. "There's a lot of inconsistency in how this unit price is broken down," says Kristin McGrath, editor and shopping expert at Offers.com. And some retailers make it easier to find than others.
What the unit price can show, though, once it's decoded, is that while buying in bulk will likely cost you more upfront, it can translate to major savings over the long run, especially if you buy the right items.
Before buying in bulk, make sure you have the space to store your extra items and that you've budgeted an extra $5 or $10 to cover costs, especially if you're making multiple bulk purchases at a warehouse club.
Here are four household goods that won't take up too much space and are definitely worth buying in bulk.
Glad Tall Kitchen Drawstring CloroxPro Trash Bags cost $13.99 for a 100-count pack of 13-gallon trash bags on Amazon, while Costco carries a similar product in bulk at $16.99 for 200. For an extra $3.50, you could get an extra 100 trash bags.
When you compare the cost per unit between both items, the brand name item costs about 13 cents per unit, while the bulk item costs 8 cents per unit: a total savings of 5 cents per unit, or almost 40%. That's a significant savings.
An 8-ounce tube of Crest Complete Whitening + Scope toothpaste costs $9.18 on Jet.com, putting the total cost per ounce at about $1.14. The same toothpaste can be purchased in bulk in a pack of five for $13.99 at Costco, though, lowering the cost per ounce to 34 cents, or approximately a 70% savings.
You should replace your toothbrush about once every three to four months, or once the bristles start fraying, according to the American Dental Association (ADA). Having extra toothbrushes encourages positive dental hygiene habits, and it'll come in handy if you ever have a friend or family member stay over for the night.
One Colgate Extra Clean toothbrush costs 99 cents at Target, but you can purchase the same brand and get six toothbrushes for just $4.39, or 73 cents per brush on Amazon. That's a 26% savings on an item you know you'll need eventually.
During the first three months of life, a baby can go through 700 diapers, according to baby registry site Babylist. Diapers are one item you want to make sure you always have on hand, and one way to make sure you never go without is to buy them in bulk. They go quick, too, so you won't have to worry about long-term storage.
A 20-pack of Pampers Swaddlers, size 1, costs $8.27, or about 41 cents per unit. Amazon carries the same brand, and parents can buy a 120-count pack for $31.10, or 26 cents per unit, which adds up to almost a 40% savings.
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