> For the complete documentation index, see [llms.txt](https://docs.payments.thalescloud.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.payments.thalescloud.io/merchant-tokenization/pci-tokenization/implement-pci-tokenization/process-a-transaction.md).

# Process a transaction

Use this flow to detokenize a PCI token during a payment.

## Flow

<figure><img src="/files/H1cIbzdSsHk8mIAmdPpw" alt=""><figcaption><p>PCI Tokenization transaction flow</p></figcaption></figure>

<table><thead><tr><th width="100">Step</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>The end user checks out in the merchant website or app.</td></tr><tr><td>2</td><td>The merchant or PSP calls <code>createTransaction</code> and provides the <code>tokenId</code>.</td></tr><tr><td>3</td><td>Thales backend performs detokenization and returns the PAN and expiry date.</td></tr><tr><td>4</td><td>The merchant or PSP sends the authorization using the PAN and expiry date.</td></tr></tbody></table>

## API

For PCI Tokenization, `tokenId` and `transactionType` are required.

Use the same `createTransaction` operation for PCI Tokenization and payment network Tokenization.

* API reference: [Create transaction](/merchant-tokenization/backend-integration/apis/server-api/transaction-management.md#post-v2-transactions)


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