---
ref: tool:instantly/reply-to-email
name: Reply to an email
company: company:instantly
workflows: []
access: [api]
tags: [capability:send-email, category:sales-engagement, has:api]
docs: https://developer.instantly.ai/api-reference/email/reply-to-an-email
updated: 2026-09-27
---

# Reply to an email

Sends a reply to an email in an Instantly inbox from one of the workspace's connected sending accounts.

Pass `reply_to_uuid` (the `id` of the email, from the email endpoints), the
sending account as `eaccount`, a `subject`, and a `body` with `html`, `text`
or both. It only replies to an existing email; it can't start a new thread.
This sends a real email, so confirm the text first.

## Set up

Use the first option your agent supports.

### API (official)

- Base URL: https://api.instantly.ai
- Endpoint: `POST /api/v2/emails/reply`
- Auth: send the header `Authorization: Bearer $INSTANTLY_API_KEY`
- Get a key: https://app.instantly.ai/app/settings/integrations
- Docs: https://developer.instantly.ai/getting-started/authorization

Before doing anything else, make one read-only call to confirm access.

## Rules

- Ask the user before anything that sends messages, costs money, or changes data.
- Never print API keys.