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

# Delegated Issuance

> A workflow in which a platform issues tax invoices via standard issuance on behalf of the supplier.

A scenario in which **a platform issues tax invoices on behalf of the supplier**, such as in logistics platforms, freelancer matching services, or marketplaces.

## Workflow

<Steps>
  <Step title="Register the supplier" icon="code">
    Call the [Register Supplier API](/api-reference/supplier/register-supplier) to register the supplier's information with Bolta. Save the `supplierKey` issued after registration.
  </Step>

  <Step title="Issue a certificate registration URL" icon="code">
    Call the [Retrieve Certificate Registration URL API](/api-reference/certificate/retrieve-certificate-registration-url) to obtain a URL where the supplier can register their certificate.
  </Step>

  <Step title="Supplier registers the certificate" icon="user-check">
    The supplier visits the issued URL and registers their certificate. This step must be performed by the supplier directly. For the redirect return and result verification after registration, see [Certificate Registration Integration](/en/api-introduction/certificate-registration).
  </Step>

  <Step title="Delegated standard issuance" icon="code">
    Call the [Issue Tax Invoice API](/api-reference/tax-invoice/issue-tax-invoice), passing the supplier's `supplierKey` in the `Supplier-Key` header. The platform uses the supplier's certificate to issue a tax invoice to the counterparty.
  </Step>

  <Step title="Receive the issuance-complete webhook" icon="zap">
    Once issuance is complete, a notification containing `taxInvoiceUrl` is sent via [webhook](/en/api-introduction/webhook-events).
  </Step>

  <Step title="Issuance-complete email" icon="mail">
    An email notifying the counterparty that a tax invoice has been received is sent automatically.
  </Step>

  <Step title="Retrieve the tax invoice (optional)" icon="search">
    Check the issuance result with the [Retrieve Tax Invoice API](/api-reference/tax-invoice/retrieve-tax-invoice).
  </Step>
</Steps>

## When It Fits

* When a logistics platform issues tax invoices on behalf of truck drivers
* When a freelancer matching service issues on behalf of freelancers
* When a marketplace automates tax invoice issuance for its sellers
* When a platform manages many suppliers
* When it is difficult for suppliers to issue tax invoices individually

## Key Points

* Use the `Supplier-Key` header to specify which supplier's certificate to use
* You need to obtain and manage a `supplierKey` for each supplier
* When a supplier's certificate expires, it must be re-registered