---
title: "Upload Contacts CSV"
description: "Get a presigned S3 URL to upload a contacts CSV for a campaign"
openapi: "POST /api/v1/s3/presigned-upload-url"
---

Uploading contacts is a two-step process. First call this endpoint to get a presigned upload URL, then PUT your CSV directly to that URL.

```bash
# Step 1: Get upload URL
curl -X POST https://your-dograh-instance/api/v1/s3/presigned-upload-url \
  -H "X-API-Key: dg_your_api_key"

# Response:
# { "upload_url": "https://...", "s3_key": "campaigns/..." }

# Step 2: Upload the CSV
curl -X PUT "https://presigned-url..." \
  -H "Content-Type: text/csv" \
  --data-binary @contacts.csv
```

Use the `s3_key` from the response as the `source_url` when [creating a campaign](/api-reference/campaigns/create).

### CSV format

The CSV must include a `phone_number` column. Any additional columns are passed as `initial_context` to each call, making them available as template variables in the workflow.

```csv
phone_number,customer_name,plan,greeting_override_type,greeting_override_text
+14155550100,Jane Smith,premium,text,Hello {{customer_name}}
+14155550101,Bob Jones,basic,text,Welcome back {{customer_name}}
```

To override the Start node greeting for a row, use these optional columns:

- Text: set `greeting_override_type` to `text` and put the message in `greeting_override_text`.
- Recording: set `greeting_override_type` to `audio` and put the public recording ID in `greeting_override_recording_id`.

Greeting text can reference other CSV columns, such as `Hello {{customer_name}}`. Empty override columns preserve the greeting configured in the Start node.