# Transaction Types

The table below describes each supported value of the `transactionType` field in the Nelnet Payments API.

| Transaction Type | Description | Notes |
|  --- | --- | --- |
| **AUTH_ONLY** | Verifies the customer has sufficient funds. Does not capture for settlement. | Requires a `CAPTURE` to complete. |
| **CAPTURE** | Submits a previously authorized `AUTH_ONLY` transaction for settlement. | Must include the `paymentTransactionId` from the original `AUTH_ONLY`. |
| **SALE** | Authorizes the transaction and if approved, marks the transaction for settlement. |  |
| **REFUND** | Refunds a prior `SALE` or `AUTH_ONLY` transaction, returning funds to the customer. | **With reference (recommended):** Requires the `paymentTransactionId` from the original transaction. **Without reference:** Used when the original `paymentTransactionId` is unavailable (e.g., during processor migration). **Note:** Some processors may not support refunds without `paymentTransactionId`. |
| **VERIFY** | Performs a zero-amount transaction to validate account information. | - **Address Verification Service (AVS):** Validates the accountholder’s billing address. Include `addressLine1` and `postalCode` in the request. The response code is returned in `processorResponse.avsResultCode`.- **Card Verification Value 2 (CVV2):** Validates the CVV2 value. Include `paymentType.cardVerificationValue` in the request. **Important:** The CVV2 value is PCI-sensitive and must never be stored. The response code is returned in `processorResponse.cvvResultCode`. |