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

# Merge Existing PDFs

> Combine generated documents with existing PDF files

This feature enables you to incorporate pre-existing PDF files into your generated documents.

<Note>
  **Availability**: Requires the Business plan or above. Only available for Airtable, Google Sheets, ClickUp, SmartSuite, Notion, and API.
</Note>

## Implementation Methods

<Tabs>
  <Tab title="Airtable / Google Sheets / ClickUp / SmartSuite / Notion">
    Designate one or more fields or columns within DocsAutomator's interface that contain the PDFs intended for merging with the generated documents.

    1. In your automation settings, find the "Merge Existing PDFs" option
    2. Select the field(s)/column(s) containing your PDF files
    3. Configure the insert position (before or after)

    When you select multiple fields, their PDFs are merged in the order you select the fields. Fields that happen to be empty on a given record are simply skipped, so optional attachments (say, a W-9 that only some vendors provide) don't block document generation.

    <Tip>
      **Airtable lookup fields**: You can also select a lookup field that references an attachment field in a linked table. This is useful when PDFs are stored in a related table rather than directly on the record.
    </Tip>
  </Tab>

  <Tab title="API">
    Pass the top-level key `existingPdfs` containing an array of one or more publicly accessible PDF URLs.

    ```json theme={null}
    {
      "docId": "your-automation-id",
      "data": {
        "customer_name": "Acme Corp"
      },
      "existingPdfs": [
        "https://example.com/terms-and-conditions.pdf",
        "https://example.com/appendix-a.pdf"
      ]
    }
    ```
  </Tab>
</Tabs>

## Configuration Options

### Insert Position

| Option                 | Behavior                                                      |
| ---------------------- | ------------------------------------------------------------- |
| Insert After (Default) | Appends additional PDFs following the generated document      |
| Insert Before          | Positions existing documents ahead of newly generated content |

### Order of Multiple PDFs

When a selected field or column holds several PDFs, they're merged in the order they appear there. This applies to every supported source. DocsAutomator does not reorder them, so changing their order at the source changes the merge order accordingly. For example, rearranging the attachments in an Airtable field, reordering the comma-separated URLs in a Google Sheets cell, or changing the order of URLs in the API `existingPdfs` array all shift the merge order to match.

### Multiple Fields

You can select more than one field or column. The merge then works field by field: all PDFs from the first selected field, then all PDFs from the second, and so on. Within each field, the order from the source applies as described above. To change the order across fields, remove the selections and re-add them in the order you want.

Empty fields are skipped. If a record has PDFs in only two of three selected fields, the document is generated with those two merged and the empty field is ignored.

## Use Cases

<CardGroup cols={2}>
  <Card title="Terms & Conditions" icon="file-contract">
    Append standard legal documents to contracts
  </Card>

  <Card title="Cover Pages" icon="file-image">
    Insert branded cover pages before generated content
  </Card>

  <Card title="Appendices" icon="files">
    Add reference documents after reports
  </Card>

  <Card title="Certificates" icon="certificate">
    Include supporting certifications with proposals
  </Card>
</CardGroup>

## Requirements

<Warning>
  * PDFs must be publicly accessible via URL (for API)
  * PDF fields must contain valid PDF files (for data source integrations)
  * Maximum file size limits may apply
</Warning>