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

# Fetch bills

> Technical step-by-step documentation to fetch bills and supplier invoices via the Maesn Unified API.

## Fetch bills from other systems in 5 steps

<Steps>
  <Step title="Authorize access" titleSize="h3">
    Your user must first authorize your application to access their accounting platform (e.g., Xero, Lexware Office, Sevdesk) via an authorization flow (e.g., OAuth, API key) through [maesn Connect](/guides/maesn-connect).
  </Step>

  <Step title="Retrieve filtered list of bills" titleSize="h3">
    Start by retrieving a list of bills by calling GET [/bills](/api-reference/accounting-endpoints/bills/get-bills) and applying the appropriate filters, for example bill date or bill status, to give your users an overview of their bills.
  </Step>

  <Step title="Show bill details" titleSize="h3">
    When the end user has selected a specific bill, present all the details including line items by calling GET [/bills/\{id}](/api-reference/accounting-endpoints/bills/get-bill).
  </Step>

  <Step title="Retrieve the bill document (optional)" titleSize="h3">
    Present original PDF documents by calling GET [/bills/\{id}/document](/api-reference/accounting-endpoints/bills/get-bill-document).
  </Step>

  <Step title="Retrieve captured bills (optional)" titleSize="h3">
    In addition, to bills created in the respective accounting platforms, bills created elsewhere and subsequently uploaded to the accounting platform can be retreived through

    * GET [/bookingProposals](/api-reference/accounting-endpoints/bookingproposals/get-booking-proposals)
    * GET [/bookingProposals/\{id}](/api-reference/accounting-endpoints/bookingproposals/get-booking-proposal)
    * GET [/bookingProposals/\{id}/document](/api-reference/accounting-endpoints/bookingproposals/get-booking-proposal-document).
  </Step>
</Steps>

<Tip>You can utilize Webhooks to make this process more efficient.</Tip>