Hi Joan,
Thanks for your question!
Yes, you will need a merchant account in order to process credit card transactions. I recommend reviewing this article that outlines which merchant accounts are compatible with Cvent: Compatible Payment Gateways
Through that article, you can submit the form to our Ecommerce team to get your merchant account set up.
Please reach out to ecommerce@cvent.com if you have further questions.
------------------------------
Sydney Langer
CSA
Cvent
------------------------------