Delay discounting, reflected in the tendency to prefer immediate rewards over delayed rewards, is associated with most forms of problematic substance use. When assessed multiple times to examine within-individual changes, for example, following acute drug administration or an intervention, shifts in delay discounting simply because of repeated assessment is a concern, particularly when the assessment task is identical. This may be true for the Monetary Choice Questionnaire (MCQ), a widely used, fixed-item assessment of delay discounting. The present research examined possible within-individual difference/equivalence of MCQ indices at test/retest. This was contrasted with within-individual difference/equivalence when using an alternate version of the MCQ at retest, specifically developed to maintain the assessment structure and scoring of the original MCQ but with different choice items. Eighty-four participants completed delay discounting at test and retest with a 1-week interval; participants were randomized to complete the MCQ at both test and retest (MCQ/MCQ; n = 43) or complete the MCQ at test and an alternate version of the MCQ at retest (MCQ/MCQ-A; n = 41). Conventional hypothesis testing indicated no significant changes in delay discounting in the MCQ/MCQ condition or MCQ/MCQ-A condition. However, equivalence analysis, which is able to established whether scores are statistically equivalent, indicated that test/retest scores were not equivalent in some cases. Specifically, only 1 magnitude in the MCQ/MCQ condition was equivalent at test/retest, whereas 2 magnitudes in the MCQ/MCQ-A condition were equivalent at test/retest. (PsycINFO Database Record (c) 2018 APA, all rights reserved).