AbstractThe primary motivation behind the advocated use of plain language in legal documents is to increase comprehension among non‐experts. We report empirical evidence regarding the effectiveness of three kinds of simplification of standard legal contracts for increasing comprehension among naïve readers. A set of legal contracts was redrafted in three stages to produce three modified versions. In the first stage we removed or replaced archaic and redundant terms; in the next stage simplified words and sentence structure were introduced; in the final stage legal terms were defined or replaced with simpler terms. Comprehension, as measured by paraphrasing and question‐answering tasks, was reliably enhanced by the use of simplified words and sentence structure, but absolute levels of comprehension were still very low. An examination of erroneous responses suggested that, quite apart from the constraints of language, non‐experts have difficulty understanding complex legal concepts that sometimes conflict with prior knowledge and b