Attaching a file in Outlook takes three steps: click the paperclip icon, find your file, and send

To attach a file in Outlook, open a new email or reply to an existing one. Look for the paperclip icon in the toolbar at the top of the compose window — it's usually near the formatting buttons. Click it, navigate to the file you want on your computer, select it, and click Open. The file name will appear in the Attachments section below the subject line. You can attach multiple files this way by repeating the process.

The exact location of the paperclip icon depends on which version of Outlook you're using, but it's always visible in the compose toolbar. If you're using Outlook on the web (the browser version), the icon appears near the bottom of the compose box. On the desktop version, it's in the top toolbar. Either way, the process is the same: click, find, select, open.

Key Takeaways

  • The paperclip icon in the compose toolbar is how you attach files in any version of Outlook.
  • You can attach multiple files to a single email by clicking the paperclip icon more than once.
  • File size limits vary by your email provider, but Outlook typically caps attachments at 20 to 25 MB per email.
  • If you can't find the paperclip icon, check that you're in the compose window and not just viewing your inbox.

Finding the paperclip icon in desktop Outlook

In Outlook on your computer, the paperclip icon sits in the ribbon at the top of the compose window. When you create a new email or click Reply, a new window opens with formatting options across the top. Scan the toolbar for the paperclip — it's usually grouped with other insert options like images and tables. The icon looks like a simple paperclip and is hard to miss once you know where to look.

If the toolbar looks crowded or unfamiliar, you may be using a newer version of Outlook that reorganizes the ribbon. In Outlook 2019 and earlier, the paperclip is under the Insert tab. In Outlook for Microsoft 365 (the subscription version), it's in the main toolbar of the compose window. Either way, it's always labeled or has a tooltip that says "Attach File" when you hover over it.

Attaching files in Outlook on the web

If you're using Outlook in your web browser, the paperclip icon appears at the bottom of the compose box, usually to the left of the Send button. Click it and your computer's file browser opens. Navigate to the file you want, click it once to select it, then click Open. The file uploads and appears in the Attachments section above the message body.

The web version works the same way as the desktop version, but the interface is slightly different. You may notice the attachment takes a moment to upload, especially if the file is large. Wait for the upload to finish before sending the email — if you send before the file finishes uploading, the recipient won't receive it.

Attaching multiple files at once

You can attach as many files as you want to a single email, as long as the total size doesn't exceed your email provider's limit. Click the paperclip icon once, select a file, and click Open. Then click the paperclip icon again and select another file. Repeat until you've attached everything you need. Each file name appears in the Attachments section as you add it.

Some versions of Outlook let you select multiple files in one go. When the file browser opens, hold Ctrl (on Windows) or Command (on Mac) and click each file you want. Then click Open once, and all selected files attach at the same time. This is faster than attaching them one by one, but not all file browsers support it — if it doesn't work, just use the one-at-a-time method.

Understanding file size limits

Outlook and most email providers limit how large a single attachment can be. The typical limit is 20 to 25 MB per file, though some providers allow up to 50 MB. If you try to attach a file larger than the limit, Outlook will warn you before you send. The warning message tells you the file is too large and suggests alternatives like using OneDrive or SharePoint to share the file instead.

If you're attaching multiple files, the total size of all attachments combined also matters. A 15 MB file and a 12 MB file together exceed the 25 MB limit on many systems. Check your email provider's attachment policy if you're unsure — you can usually find it in the Help section of your email account. If a file is too large, compress it using your computer's built-in zip tool, or ask the recipient if they can receive it through cloud storage instead.

What to do if the attachment doesn't appear

If you clicked the paperclip icon but the file didn't attach, the most common reason is that the file browser closed without you selecting anything. Click the paperclip icon again and make sure you navigate all the way to the file, click it once to highlight it, and then click the Open button. Don't just double-click the file — that sometimes closes the browser instead of attaching the file.

Another reason attachments fail is if your internet connection drops while the file is uploading, especially in the web version of Outlook. If this happens, try attaching the file again. If the problem persists, try a different file to see if the issue is with that specific file or with your connection. If a different file attaches fine, the original file may be corrupted or in a format your email system doesn't support.

Removing an attachment before sending

If you attached the wrong file or changed your mind, you can remove it before sending. Look at the Attachments section below the subject line — you'll see the file name with an X or delete button next to it. Click the X to remove the attachment. The file stays on your computer; removing it from the email just means it won't be sent to the recipient.

You can remove attachments one at a time, or remove all of them if you decide not to send any files. There's no penalty for attaching and then removing — it only affects what the recipient sees when they open the email.

Frequently Asked Questions

Can I drag and drop a file directly into the email instead of using the paperclip icon?

Yes, in most versions of Outlook you can drag a file from your computer directly into the compose window. Open the file browser on your computer (File Explorer on Windows or Finder on Mac) and drag the file into the email body or the Attachments section. This works the same way as clicking the paperclip icon, just faster if you already have the file visible.

What happens if the recipient's email doesn't support large attachments?

Most modern email systems support attachments up to 25 MB, but some older systems or corporate email servers may have smaller limits. If the recipient's system rejects your attachment, they'll usually get a bounce-back message. In that case, try compressing the file or using cloud storage like OneDrive, Google Drive, or Dropbox to share it instead.

Can I attach files from OneDrive or SharePoint without downloading them first?

Yes. In Outlook, click the paperclip icon and look for an option to browse OneDrive or SharePoint. This inserts a link to the file rather than attaching the file itself, which saves space and keeps the file up to date if you make changes. The recipient can open the link and view the file directly.

Why does Outlook sometimes ask me to confirm before sending an email with attachments?

Outlook has a safety feature that reminds you if the email mentions an attachment but you haven't actually attached a file. For example, if you write "See the attached document" but forget to attach anything, Outlook will ask if you meant to include a file. This prevents you from sending incomplete emails by accident.

Can I attach a file that's currently open in another program?

Yes, you can attach a file even if it's open in Word, Excel, or another program. The file on your computer is what gets attached, not the version currently in memory. If you've made changes to the file but haven't saved them, save the file first to make sure the recipient gets the latest version.