The first operational administration of the Partnership for Assessment of Readiness for College and Careers (PARCC) took place during the 2014-2015 school year. In addition to the traditional paper-and-pencil format, the assessments were available for administration on a variety of electronic devices, including desktop computers, laptop computers, and tablets. This report describes a study of the comparability of PARCC assessments administered on tablets and non-tablet devices, such as notebook and desktop computers. The goal of this study was to investigate whether assessment tasks were of similar difficulty on tablets and non-tablet devices, whether the psychometric properties of test scores were similar when comparing testing on tablets and non-tablet devices, and whether overall test performance was similar for students testing on tablets and non-tablet devices. This study examined performance on eight PARCC assessments: grade 5 mathematics, grade 7 mathematics, Algebra 1, Geometry, Algebra 2, grade 3 English language arts/literacy (ELA/L), grade 7 ELA/L, and grade 9 ELA/L. Any student who took one of the study forms on a tablet or non-tablet device in spring 2015 was eligible for inclusion in this study. Students were matched on demographic variables to create samples that would be comparable, thereby providing an unbiased comparison of performance on tablet and non-tablet devices. Overall, this study revealed consistent evidence of comparability between testing on tablets and non-tablet devices.