> ## Documentation Index
> Fetch the complete documentation index at: https://docs.slm.m1amdocs.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Working with One-Time Transactions

Subscribe Billing Events occur when an AutoBill generated event passes through your payment processor. A Billing Event might be a recurring or one-time transaction, a manually accepted and entered payment, a credit check (for credit cards), a bank withdrawal (EDD), or a customer refund.

One-Time Transactions may be generated for a single item purchase, or for the first in a series of recurring billings. Note that some payment methods, supported by Subscribe, do not allow recurring transactions, and allow only one-time transactions.

While AutoBill payments are also processed as Subscribe Transactions, this chapter deals specifically with the `Transaction` object, with an emphasis on one-time purchases. For more information on recurring billing, see [Working with AutoBills](ProgGuide_AutoBills#).

**Note:** Use of the forward slash character (/) in merchant identifiers is not allowed. See [Merchant Identifiers](Merchant_Identifiers#) for more information.

Subscribe allows you to issue email notifications when these events occur. For more information, see [Customer Notifications](ProgGuide_CustomerNotifications).

* **[Setting Up Real-Time Billing for One-Time Purchases](../topics/Setting_Up_Real_Time_Bil)**

* **[Using Credit Cards for One-Time Transactions](../topics/Using_Credit_Cards_for_O)**

* **[Using Carrier Billing for One-Time Transactions](../topics/Using_Carrier_Billing_fo)**

* **[Using Boleto Bancario for One-Time Transactions](../topics/Using_Boleto_Bancario_fo)**

* **[Using ECP for One-Time Transactions](../topics/Using_ECP_for_One_Time_T)**

* **[Using EDD and UK DD for One-Time Transactions](../topics/Using_EDD_and_UK_DD_for__1)**

* **[Using PayPal for One-Time Transactions](../topics/Using_PayPal_for_One_Tim)**

* **[Recording a Payment Manually](../topics/Recording_a_Payment_Manu)**

* **[Importing Transactions from other Billing Systems to Subscribe](../topics/Importing_Transactions_f)**

* **[Refunding Customers](../topics/Refunding_Customers)**


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