Authorize.net currently does not offer an automated way to distinguish between different sources of transactions. However, there are several strategies that can help to differentiate one set of transactions from another:

1. Invoice Numbers: The most common strategy is to use unique invoice numbers. Some e-commerce platforms allow you to set up an invoice number prefix, which lets you add letters or numbers to the start of the invoice numbers. For instance, you could place "WEB" before the invoice number generated by the platform. This method is beneficial because invoice numbers can be used in searches. To locate all transactions with an invoice number starting with "WEB", you can go to the Search tab in the Merchant Interface and type "WEB*" in the Invoice # field. Please check if your e-commerce platform supports invoice number prefixing. If a web developer has created your platform, they can likely implement this feature. The field used to submit invoice numbers to Authorize.net is called x_invoice_num.
2. Description Field: Another method is to use the Description field (x_description) to indicate whether a transaction was entered manually or submitted from the website. This field isn't searchable, so to use this option, you need to download your transaction history into a text file that you can import into Excel or another application. To learn how to download the transaction history and import it into Excel, refer to the article: How can I download and view my transactions in another application such as excel?
3. Customer IP Address: A third option, which we recommend, is to ensure your website is posting the Customer IP Address (x_customer_ip) to us. This field is never set for Virtual Terminal transactions, so the presence of a Customer IP Address indicates that it came from your website. Having the Customer IP Address can also help prevent and report suspicious transaction activity. It also allows you to utilize our Advanced Fraud Detection Suite more fully. Like the Description field, the Customer IP Address is not searchable, but can be seen by downloading the transaction history as mentioned above.