Background: Each year, millions of people develop suicide plans. These plans are assumed to indicate imminent suicide risk, yet this has rarely been tested. The present study seeks to address two questions: (1) how prevalent are specific thoughts of suicide plans among individuals with a history of suicidal thoughts and behaviors and (2) do suicide plans confer risk of future suicide attempts in the short term? Methods: Secondary data analysis was performed on a longitudinal dataset (N = 1021). Prevalence and frequencies of suicide planning features (i.e., method, time, place) at baseline and 3, 14, and 28 days post-baseline were calculated. Logistic regressions were conducted to assess whether suicide plans confer risk of suicide attempts across a 28-day follow-up period. Results: Suicide planning more commonly involved thoughts of method than place and/or time. High variability in suicide planning was evident and thoughts of suicide plans frequently recurred. Contrary to assumptions, suicide plans displayed weak associations with nonfatal suicide attempt across the 28-day follow-up period. Conclusions: Suicide plans appear heterogeneous in nature. They do not appear to play a strong role in predicting nonfatal suicide attempts. Re-evaluation of the central role that suicide plans occupy within clinical risk assessments may be warranted.