Costco notes that both potential and existing employees must comply with the company’s drug and alcohol testing policy. Costco is committed to keeping a drug and alcohol-free workplace.
They note that testing may occur in any of these four scenarios: Pre-Employment, Reasonable Suspicion (i.e. appearing under the influence at work), Post-Accident, and in Return to Duty. There is nothing mentioned about random drug testing, but with such a stringent policy, it makes sense to be on alert at all times.