---
title: "Upload documents to sign"
method: POST
path: "/v1/onboarding/signatures/{workflowId}/documentsToSign"
tags: ["Qualified Electronic Signature"]
---

# Upload documents to sign

`POST /v1/onboarding/signatures/{workflowId}/documentsToSign`

Use this endpoint for Qualified Electronic Signature workflows to upload the document(s) to sign. <br /><br /><img src="https://files.readme.io/310d4d3-Inline_Caution.svg" align="left" alt="Important" /> **Important:** <br />• Before using this endpoint, see the <a href="https://docs.fourthline.com/docs/qes-integration">integration guide</a>. <br />• <code>signatureId</code> and <code>workflowId</code> are string identifiers that can be used interchangeably. <br />• Documents can be uploaded in parallel as long as each document uses a unique `document_id`.<br />• Requests around **26 MB** may hit the default request size limit.<br />• For optimal reliability and experience, we recommend keeping the number of documents per signature low (typically two or three).<br />• A successful response is empty.

## Path parameters

- `workflowId` string, required

## Headers

- `Authorization` string, required — The `access_token` returned in your most recent [Create access token](https://docs.fourthline.com/reference/create-access-token) response.
- `Content-Type` string

## Response `202`

Documents upload accepted

- object — The request was accepted. The response body is empty.

## Other responses

- `400` — Invalid request parameters
- `404` — Signature not found
- `409` — Conflict
- `422` — The request could not be processed

---

[API](https://skmtc.net/fourthline/apis/fourthline-apis.md) · [All operations](https://skmtc.net/fourthline/apis/fourthline-apis/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/fourthline/fourthline-apis/revisions/7991ae7c8383/schema)