In the U.S., 18,800 lives could be saved annually if those advised to obtain colorectal screenings based on national guidelines complied (Zauber et al., 2012). Subtle suggestions embedded in a decision-making environment can change people's choices (Thaler and Sunstein, 2008). Past research has shown that prompting people to form plans about where and when they will complete an intended behavior increases engagement in activities ranging from voting to vaccination (Gollwitzer and Sheeran, 2006; Milkman et al., 2011; Nickerson and Rogers, 2010). When plans are formed, they link intended behaviors with a concrete future moment and course of action, creating cues that reduce forgetfulness and procrastination. We studied whether planning prompts increase colonoscopy rates.