# colis or an email attachment?

> Nothing to set up, but no preview, no receipt and no structured answer. Where an email attachment and colis overlap, where they differ, and when each is enough.

Canonical: https://colis-site.vercel.app/en/alternatives/piece-jointe · Markdown: https://colis-site.vercel.app/en/alternatives/piece-jointe.md · Français: https://colis-site.vercel.app/alternatives/piece-jointe

For a light file and a responsive client, an attachment is enough. colis adds what an attachment cannot say: whether the file was opened, which version was approved, and the client’s answer in a form a script can read.

## An email attachment
Attach the file to an email. Nothing new for anyone: your client already knows how to open it, and the conversation stays in the thread.

## Where they part ways.
| | colis | An email attachment |
| --- | --- | --- |
| Where the file lives | Your bucket: S3, R2, MinIO, Scaleway, Wasabi | The sender’s and the recipient’s mailboxes |
| Knowing it was opened | Sent, opened, approved or changes, each with its time | None, unless the recipient agrees to send a read receipt |
| The client’s answer | Approve, or ask for changes with a comment, from the pickup page. Once, for good | A reply in the thread, in free text |
| Starting an automation | A signed webhook at every step, and an n8n node | Mail rules, depending on your email client |
| Large files | Straight from the browser to the bucket in parts, resumable; 2 GB by default | Capped by each side’s mail server |
| What the client needs | Nothing: a code or a link | An email address |
| When it goes away | When you say: ten minutes to your maximum, or at the first download | When each side deletes the message |

## What actually changes.
- **Size** — An attachment is capped by the mail servers on both sides. The delivery page sends large files straight to your bucket, in parts, and resumes an interrupted upload.
- **Which version was approved** — With colis each version is its own parcel, with its own code and its own verdict. “Fine by me” in a thread does not say which attachment it answers.
- **The file stays yours** — An attachment lives in two mailboxes for as long as they keep it. A parcel lives in your bucket until its expiry, and a lifecycle rule deletes it.

## Pick the one that fits.
### Keep an email attachment when
- The file is light and the client is used to email
- You need no trace of the approval
- Nobody should have anything new to open

### Pick colis when
- You want to know the client opened it, and when
- The approval, or the changes asked, should be one click and on record
- The file is heavy, or should not sit in a mailbox
- The answer should start something: an invoice, a ticket, a message