> ## Documentation Index > Fetch the complete documentation index at: https://docs.crossmint.com/llms.txt > Use this file to discover all available pages before exploring further. # Process Payment > Associates the broadcast on-chain stablecoin deposit with an offramp order by its transaction ID. This call is **optional**: the prepared transaction returned by Create Order already carries the order memo, so Crossmint matches the deposit to the order automatically once it is broadcast. Use this endpoint to explicitly attach the deposit transaction to the order (for example when you broadcast the transfer yourself and want to report the transaction ID immediately rather than waiting for automatic matching). **Authentication**: Use either a server-side API key with the `orders.update` scope, or the `clientSecret` returned when the order was created, passed as an `Authorization` header. ## OpenAPI ````yaml post /2022-06-09/orders/{orderId}/payment openapi: 3.0.1 info: description: | N/A version: 1.0.0 title: Headless Checkout contact: name: Crossmint Headless Checkout APIs url: https://www.crossmint.com email: support@crossmint.com servers: - url: https://staging.crossmint.com/api description: Staging environment (testnets) - url: https://www.crossmint.com/api description: Production environment (mainnets) security: [] tags: - name: Headless Checkout description: APIs to use the headless checkout paths: /2022-06-09/orders/{orderId}/payment: post: tags: - Headless summary: Process Payment description: > Process payment for an order using a crypto transaction ID. **Authentication**: Use either a server-side API key with `orders.update` scope, the `clientSecret` from order creation as an authorization header, or a JWT token with `orders.create` scope. operationId: process-payment parameters: - $ref: '#/components/parameters/orderId' requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/ProcessPaymentInput' responses: '200': description: Payment processed successfully. content: application/json: schema: $ref: '#/components/schemas/OrderObject' '400': description: >- Invalid arguments, please make sure you're following the api specification. content: application/json: schema: $ref: '#/components/schemas/400Response' '403': description: Forbidden error, please ensure the credentials are correct. content: application/json: schema: $ref: '#/components/schemas/403Response' '404': description: Not found error. content: application/json: schema: $ref: '#/components/schemas/404Response' '503': description: >- Please try again in a few minutes. If the issue still persists, contact Crossmint support. content: application/json: schema: $ref: '#/components/schemas/503Response' '524': description: A timeout occurred. content: application/json: schema: $ref: '#/components/schemas/524Response' security: - apiKey: [] - orderClientSecret: [] components: parameters: orderId: name: orderId in: path description: | This is the identifier for the order with UUID format. **Example:** `9c82ef99-617f-497d-9abb-fd355291681b` required: true schema: type: string schemas: ProcessPaymentInput: type: object title: Crypto Payment description: >- Process payment using a crypto transaction ID. Use this when the user has already submitted a crypto transaction. properties: type: type: string enum: - crypto-tx-id description: The type of payment being processed example: crypto-tx-id txId: type: string description: The transaction ID of the crypto payment example: 5UfgJ7vVFmH8K9YxLmNpQrStWvXyZaBcDeFgHiJkLmNoPqRsTuVwXyZaBcDeFgHiJkLm required: - type - txId additionalProperties: false OrderObject: type: object properties: orderId: type: string example: b2959ca5-65e4-466a-bd26-1bd05cb4f837 phase: type: string example: payment locale: type: string example: en-US lineItems: type: array items: type: object properties: chain: type: string example: polygon-amoy executionMode: type: string enum: - exact-out - exact-in description: >- Execution mode for the line item. 'exact-out' is used for NFT purchases. 'exact-in' is used for token or memecoin purchases. example: exact-out quantity: type: number example: 1 callData: type: object properties: quantity: type: number example: 1 ADDITIONAL_PROPERTIES: type: string example: Your other mint function arguments executionParams: type: object description: >- Raw mint arguments for exact-in token or memecoin purchases. Only present when executionMode is 'exact-in'. additionalProperties: true maxSlippageBps: type: string description: >- Slippage tolerance in basis points. Only present when executionMode is 'exact-in'. example: '50' metadata: type: object properties: name: type: string example: Headless Checkout Demo description: type: string example: NFT Description imageUrl: type: string example: https://cdn.io/image.png quote: type: object properties: status: type: string example: valid charges: type: object properties: unit: type: object properties: amount: type: string example: '0.0001' currency: type: string example: eth salesTax: type: object description: Sales tax applied to physical product purchases properties: amount: type: string example: '0.34' currency: type: string example: usdc shipping: type: object description: Shipping costs for physical product purchases properties: amount: type: string example: '0' currency: type: string example: usdc totalPrice: type: object properties: amount: type: string example: '0.0001' currency: type: string example: eth delivery: type: object properties: status: type: string enum: - awaiting-payment - in-progress - completed - failed description: >- Status of the delivery. 'awaiting-payment': Initial state before payment is made. 'in-progress': Payment received, transaction submitted but not yet completed. 'completed': Successfully delivered with transaction ID and tokens. 'failed': Delivery failed, typically for refunded transactions. example: awaiting-payment rail: type: string enum: - rtp - fednow - ach-same-day - ach-us - wire - sepa-instant - sepa - spei - ach-co description: >- Bank rail the payout was routed over. Present on offramp orders once routing has resolved; immutable thereafter. completedAt: type: string format: date-time description: >- ISO 8601 timestamp when the fiat payout reached its terminal success signal at the rail. Offramp orders only; present once the delivery is completed, and preserved if a completed payout is later returned. Approximate on delayed rails (ACH, standard SEPA). example: '2026-07-27T20:35:00.000Z' recipient: type: object properties: locator: type: string example: email:: email: type: string example: testy@crossmint.com walletAddress: type: string example: 0x1234abcd... txId: type: string description: >- The blockchain transaction ID. Only present when status is 'completed'. example: >- 0x2e69f11dae7869b92e3d5eaf4cadd50c48b5c6803d1232815f979d744521ad4c tokens: type: array description: >- Array of tokens delivered. Only present when status is 'completed'. items: type: object properties: locator: type: string description: >- Universal token locator in the format chain:address:tokenId example: polygon:0xE04Cf294985282Ddc088E6433c064cfB85eD9EdA:3 contractAddress: type: string description: The contract address (EVM chains) example: '0xE04Cf294985282Ddc088E6433c064cfB85eD9EdA' tokenId: type: string description: The token ID (EVM chains) example: '3' mintHash: type: string description: The mint hash or address (Solana) example: MintHashAbc123 quantity: type: string description: >- The quantity of tokens delivered in smallest units (optional, only for fungible tokens in exact-in mode) example: '1500000' symbol: type: string description: >- The token symbol (optional, only when quantity is present) example: USDC decimals: type: number description: >- The number of decimals for the token (optional, only when quantity is present) example: 6 quote: type: object properties: status: type: string enum: - valid - expired - all-line-items-unavailable - requires-physical-address description: >- Status of the quote. 'requires-physical-address' indicates that a shipping address is required for physical products. example: valid quotedAt: type: string example: '2024-06-07T16:55:44.653Z' expiresAt: type: string example: '2024-06-07T17:55:44.653Z' totalPrice: type: object properties: amount: type: string example: '0.0001375741' currency: type: string example: eth payment: type: object properties: status: type: string enum: - requires-kyc - failed-kyc - manual-kyc - awaiting-payment - requires-recipient - requires-crypto-payer-address - failed - in-progress - completed description: >- Status of the payment. View the status codes for more information. example: awaiting-payment method: type: string example: base-sepolia currency: type: string example: eth preparation: type: object properties: chain: type: string example: base-sepolia payerAddress: type: string example: 0x1234abcd... serializedTransaction: type: string example: 0x02f90..... receiptEmail: type: string description: Email address that the receipt will be sent to. example: user@example.com received: type: object description: Payment amount received. Present when payment is completed. properties: amount: type: string example: '0.50' currency: type: string example: usd refunded: type: object description: Refund amount and currency. Present when a refund was issued. properties: amount: type: string example: '0.50' currency: type: string example: usd failureReason: type: object description: >- Reason for payment failure. Present when payment status is 'failed'. properties: code: type: string example: payment-declined message: type: string example: The payment was declined by the issuer. 400Response: type: object properties: error: type: boolean example: true message: type: string description: Human-readable error message describing what went wrong code: type: string description: Machine-readable error code for programmatic handling enum: - single_purchase_exceeded - daily_transaction_exceeded - token_daily_volume_exceeded parameters: type: object description: Additional parameters providing context for the error properties: amount: type: string description: Transaction amount that caused the error limit: type: string description: The limit that was exceeded hoursUntilReset: type: string description: Hours until the limit resets remainingAmount: type: string description: Remaining amount available before hitting the limit 403Response: type: object properties: error: type: boolean example: true message: type: string example: Malformed API key. / API key provided doesn't have required scopes. 404Response: type: object properties: error: type: boolean example: true message: type: string example: Not found 503Response: type: object properties: error: type: boolean example: true message: type: string example: >- Please try again in a few minutes. If the issue still persists, contact Crossmint support. 524Response: type: object properties: error: type: boolean example: true message: type: string example: A timeout occurred. securitySchemes: apiKey: type: apiKey name: X-API-KEY in: header orderClientSecret: type: apiKey name: Authorization in: header ````