When you see an ad that promises to save you “up to 30%,” do you assume that means that you will see a savings of 30%? You’re reading Consumerist, so you’re probably thinking “Duh, of course not.” But a new study shows that a large number of consumers are not discerning between conditional “up to” promises and unconditional performance statements.

The Federal Trade Commission recently commissioned a study that looked out how consumers perceive and comprehend the “up to” conditional in advertisements.

The researchers used different versions of an ad for windows — one that stated that the windows were “proven to save up to 47% on heating and cooling bills,” and one that simply stated, “proven to save 47%.”

Of those who looked at the “up to” version, 45.6% mistakenly said the ad promised to save 47%. Meanwhile, only 58.3% of consumers who saw the unconditional version said the ad promised to deliver 47% savings. According to the FTC, the small difference between the two results indicates that the use of “up to” did little-to-nothing to change consumers’ perception that the ad was promising the maximum level of performance.

Consumers were also asked a question about whether the ads promised to deliver savings to “all,” “almost all,” or “most” customers. 28.1% of those who had looked at the “up to” ad answered “all” or “almost all,” while nearly the same exact number (27%) of those who saw the unqualified ad responded similarly.

The FTC believes that the results of the study show that too many consumers are misinterpreting or just not glossing over the “up to” qualification when they see it in an ad.

As last year’s Federal Communications Commission broadband study showed, several Internet service providers are not consistently delivering on their “up to” download speeds, though many of them tout these maximum speeds in their ads and marketing materials.

“These figures indicate that a substantial percentage of consumers interpreted this ‘up to’ claim to say that a majority of users would receive the maximum promised results,” writes the FTC staff attorney Serena Viswanathan in a statement to Consumerist. “This data supports the FTC’s view that advertisers making similar claims should be able to prove that consumers are likely to get the maximum results promised under normal circumstances.”

You can check out a PDF of the entire report HERE.

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