---
title: Attachments by appID
slug: apis/lending/application-decisioning/attachments-by-appID
description: Upload ZIP document packages to the Preapproval API using application_id, with support for loan, credit, underwriting, and BSA-AML files.
icon: {"apiMethod":"POST"}
docTags: 
createdAt: 2025-07-21T09:45:55.285Z
---

## Preapproval API: Upload supporting files

This new preapproval API allows you to upload supporting files associated with an application. 

The identifier of the application set is the application\_id that is created for each application in the partner's system, and has been sent in to pre-approval. 

:::ApiMethodV2
```json
{
  "name": "Endpoint: /v2/applications/by-app-id/{id}/attachments",
  "method": "POST",
  "url": "https://lendingsandbox.crbcos.com/preapproval/v2/applications/by-app-id/{application_ID}/attachments",
  "description": "Upload a collection of attachments to an application that has been sent into pre-approval v2",
  "tab": "examples",
  "examples": {
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  "request": {
    "pathParameters": [],
    "queryParameters": [],
    "headerParameters": [],
    "bodyDataParameters": [
      {
        "name": "id",
        "kind": "required",
        "type": "string",
        "description": "The identifier of the application set is the application_id that is created for each application in the partner's system, and has been sent in to pre-approval.",
        "": "The identifier of the application set is the application_id that is created for each application in the partner's system, and has been sent in to pre-approval."
      }
    ],
    "formDataParameters": [
      {
        "name": "attachment",
        "kind": "required",
        "type": "string",
        "description": "The zip file (see important note below) should include all documents that a client submits with an application and all documents the partner sends back to the client for this application.",
        "": "required"
      }
    ]
  },
  "currentNewParameter": {
    "label": "Form Parameter",
    "value": "formDataParameters"
  },
  "autoGeneratedAnchorSlug": "endpoint-v2applicationsby-app-ididattachments",
  "legacyHash": "tgQRBebkaP-DPVVBWYCxR"
}
```
:::

:::hint{type="warning"}
**IMPORTANT**
The zip file should contain the complete document package. This includes:

- The loan agreement
- AAN
- Credit report
- Relevant documents or responses from vendors used to decision the application according to your credit underwriting policy as well as your BSA-AML processes
- Any data point used as input to your model

For a list of acceptable attachment naming conventions, please refer to  [File Naming convention](docId\:uRkNIHuM7qYLQdCEE7tU-) 
:::

The API is available in the latest Postman collection and in the [Swagger documentation](https://lendingsandbox.crbcos.com/preapproval/v2/swagger/index.html).