In this meta-analysis of single-case designs, the researchers investigated the effects of word-problem instruction for students with learning disabilities in Grades 1 through 12, as reported in 20 peer-reviewed articles published between 1975 and 2020. A two-level multilevel model with a robust variance estimation method was implemented to calculate the effect sizes. A significant overall effect of word-problem instruction for students with learning disabilities was found, and the results indicate that studies meeting all three quality indicators of implementation fidelity (i.e., adherence, dosage, and regularity) showed greater effects. The average weighted effect sizes of word-problem instruction varied depending on the content and practice standards of the Common Core State Standards for Mathematics. Limitations and future research directions are also discussed.