Short vs. Long Copy on Guarantees

We know that one way improve your ability to convince someone of something is to pile on the information.

Surprising, short, simple copy, can sometimes work better on specific things (e.g., guarantees).

A test of guarantee text at the end of an online order form compared the performance of these two guarantees:

“You may cancel at any time.”

vs. this personalized version with additional reassurances:

“John, your satisfaction is fully guaranteed. If VetFriends is not what you had in mind, feel free to cancel at any time – we are here to serve you.”

The short copy converted 14.5% better than the longer copy.


We've seen that long, hard to read text extends the apparent effort and time for an activity (see Convince with Simple Fonts). I think in this case, it's likely that the small, dense block of text in the longer offer subliminally suggested to readers that cancellation might be a hassle. The six-word guarantee, on the other hand, communicated that cancellation would be speedy and simple.

Continue Reading@ neuroscience marketing

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