What is the PayPal transaction ID? Where can I find it? Solution A PayPal transaction ID is a 17-character string (letters and numbers) that is used to identify a single PayPal transaction. All transactions have an unique transaction ID associated to them. You can use the Transaction ID to track the status of transactions, or to search for past transactions. If you have purchased any of our apps and want to know the transaction ID associated to that transaction, you can find it in the «Receipt for Your Payment to MobileInnovations» email that PayPal sends to you after purchasing the license. You can also find it in your PayPal account overview, selecting the transaction details of your payment to MobileInnovations. Please note that some transaction receipts may have a Receipt No. instead of a Transaction ID.