# How to Send an Envelope

There are **two ways to send an envelope using the Signable API**, depending on the type of workflow you're building:

1. **Upload a document directly**
2. **Use a Template**


Each approach gives you flexibility in how documents, fields, and signers are handled.

> 💡 **If you're new to the API**
Before continuing, make sure you're authenticated. See the [Authentication guide](/authentication) for instructions on using your API key.


Only one document input method can be used per request.
For example, you cannot upload a document and also provide a template fingerprint.

## 🔄 Choosing the right approach

| Method | Best for | Flexible fields? |
|  --- | --- | --- |
| **Uploaded Document** | One-off or ad-hoc documents | Yes (via tags) |
| **Template** | Reusable forms you send often | Yes (prefill via merge fields) |


## 📚 Available guides

- [Send an Envelope with an Uploaded Document](/guides/send-envelope-uploaded-document)
- [Send an Envelope Using a Template](/guides/send-envelope-template)


Each guide includes step-by-step instructions, example payloads, and recommendations for best results.