An area of particular importance when examining index scores on the Wechsler Intelligence Scale for Children--Fifth Edition (WISC-V) is the utilization and interpretation of critical values and base rates associated with differences between an individual's subtest scaled score and the individual's mean scaled score for an index. For the WISC-V, critical value and base rate information is provided for the core subtests contained within each of the primary indices. However, critical value and base rate information is not provided by the test publisher for subtests within the Quantitative Reasoning Index (QRI), Auditory Working Memory Index (AWMI), Nonverbal Index (NVI), General Ability Index (GAI), Cognitive Proficiency Index (CPI), Naming Speed Index (NSI), Symbol Translation Index (STI), and Storage and Retrieval Index (SRI). This study investigates and provides critical values and base rates for performance on the QRI, AWMI, NVI, GAI, CPI, NSI, STI, and SRI.