Working memory capacity plays a major role in many applied contexts, and it is important to be able to accurately measure this construct. The current studies tested whether the modality of administration of the letter-number sequencing task affects performance on the task. The letter-number sequencing task is a working memory capacity measure included as part of the Wechsler Adult Intelligence Scale-III and Wechsler Adult Intelligence Scale-IV test batteries. The task involves hearing a series of letters and digits, and then reporting back the stimuli with the letters in alphabetical order and digits in ascending numerical order. The task is traditionally administered orally, but recent studies have administered versions of the tasks visually by displaying stimuli on a computer screen. Results suggest that performance differences on the letter-number sequencing task may arise as a function of language background and task administration modality.