Can I pay by credit card after I have already been issued an invoice? Erryn Leavell Updated July 18, 2019 23:09 Follow Invoice Payment Options Yes you can. Once you receive your invoice, payment by credit card will be available. Related articles What methods of payment do you accept through the OETC Shop? How do I purchase from the OETC Shop? How do I renew my OETC Membership? How do I update items or quantities on a quote in the OETC Store? How do I get a complete purchase history report for my institution?