This report summarizes one of the invited papers to the ConfChem online conference on Mathematics in Undergraduate Chemistry Instruction, held from October 23 to November 27, 2017, and hosted by the ACS DivCHED Committee on Computers in Chemical Education (CCCE). Combining data collected by a team of nine instructors from six Texas institutions for an IRB-approved investigation, this research correlated the arithmetic skills of first-year general chemistry students (n = 2127) to final course grades. The validated, highly reliable (KR-21 = 0.821) instrument, named the Math-Up Skills Test (MUST), evaluated the following topics using 16 questions: multiplication, division, fractions, scientific notation, exponential notation, logarithms, square roots, and balancing chemical equations. The MUST was given twice to each student: first without the use of a calculator followed by a similar, modified version with the use of a calculator. Outcomes suggest that general chemistry students’ arithmetic skills are more correlated with course grades when calculators are not used than when calculators are used. Perhaps more emphasis should be placed on improving students’ mathematics automaticity.