Don't overpay for sunscreen

When you buy a twin pack or "value size" of sunscreen, you're getting a better deal than if you were to purchase a single bottle, right? Not necessarily. When Consumer Reports sent our secret shoppers to 24 stores in four different states, we discovered that you might actually pay more. Here's what we found.

• An 8-ounce bottle of Banana Boat Sport Performance SPF 30 lotion was priced at $6.49 and a twin pack of 8-ounce bottles cost $13.78 at a Target store in Troy, Mich. Ounce for ounce, you pay more for the twin pack—86 cents per ounce vs. 81 cents per ounce for the single bottle.

Learn everything you need to know about sunscreen before buying it—and make sure you know how to use sunscreen correctly.

• A 10-ounce "value size" bottle of Equate Kids Sunscreen Continuous Spray SPF 50 cost $7.98 (80 cents per ounce) at a Walmart in Phoenix. But here's a case where doubling up makes sense: a twin pack containing two 6-ounce bottles cost $8.98, 75 cents per ounce. Ditto for Coppertone Ultra Guard SPF 30 at the same store. A 9.5-ounce bottle cost $9.88—$1.04 per ounce. The twin pack of two 6-ounce bottles costs $11.97, or $1 an ounce.  At Walgreens, its 6-ounce Well at Walgreens Sport SPF 30 spray costs $8.29. But if you buy the double pack it's $11.99. That's $1.38 per ounce vs. $1 an ounce.
  
  
• Sometimes there's no price difference at all between the regular size and the twin pack or value size when you compare the actual amount of product you're getting. For instance, Target's Up & Up Sport 30 costs $9.99 for two 6-ounce bottles or 83 cents per ounce, whereas a single 6-ounce bottle costs $4.99—which also comes out to 83 cents  per ounce.

So before you head to the register, do a little math to make sure you're not overpaying. And if your calculations do show that value size or twin pack is the better deal, consider the sunscreen's expiration date. If you don't think you'll use all of the product before it expires, then pick up the smaller size.

—Susan Feinstein