Can I use my Mastercard at merchants that do not accept Mastercard credit cards (i.e.Costco)? May 20, 2020 23:20 Updated Yes, you can use your new Money Debit Mastercard at Costco and anywhere else that accepts debit cards. Related articles How should I update my new Mastercard info on Apple Pay, Samsung Pay, Amazon, etc? What are the benefits of the new Mastercard debit card? Why has my Visa card stopped working? What do I need to do before I receive my new Mastercard? Is SoFi Money a checking or savings account?