What is a merchant ID? Leroy Esterhuizen August 13, 2021 05:59 Updated Follow Each Adumo Online merchant is issued with a Aumo Online Merchant ID. This identifies the merchant on Adumo Online's Back Office system. Related articles What is TPR? How do I Manage my account? Which application ID should I use for 1 Click? Where can I find sample code for Enterprise with 3D Secure? What is an application ID? Comments 0 comments Please sign in to leave a comment.