Purpose -The purpose of this paper is to evaluate a mail-based educational intervention to improve knowledge of blood pressure and cholesterol values among members of a large insurance population. Design/methodology/approach -As part of the 2004 health risk appraisal (HRA) follow-up program, 48,429 members of WEA Trust received at least two mailings for the mail-based blood pressure and cholesterol intervention. These members then completed a follow-up HRA in 2006. Change in the knowledge and risks of blood pressure and cholesterol values were analyzed among two-time participants. A survey was also completed six to nine months after the first mailing to study participants' awareness and perception of the program. Findings -The 2004 and 2006 two-time HRA participants showed a 13.9 percentage point gain (p , 0.05) and 12.2 percentage point gain (p , 0.05) in people who knew their blood pressure and cholesterol values, respectively, as well as a significant increase in the percent of people taking medication or under medical care for their blood pressure (þ2.9 for overall and þ 11.3 for BP $ 140/90 population; p , 0.05) or cholesterol conditions (þ3.8 for overall and þ11.4 for cholesterol $ 240 population; p , 0.05). Among those who knew their values (BP or cholesterol) in both 2004 and 2006, there was a 3.9 percentage point increase (p , 0.05) in the number of people with normal BP (BP , 120/80 mmHg) and a 4.8 percentage point increase (p , 0.05) in the number of people with normal cholesterol (cholesterol ,200 mg/dL) in 2006. The majority (83 percent) of survey respondents found the materials useful for improving health and 22 percent contacted a physician because of the information they received.Practical implications -This relatively low-cost and easily implemented educational intervention was successful in increasing knowledge of blood pressure and cholesterol values, taking control of blood pressure and cholesterol risks and in encouraging appropriate follow-up with a physician. Originality/value -Knowledge of blood pressure and cholesterol numbers are an important first step in raising awareness of a person's health risks and disease status.