Guides · Attachments
Can you mail merge with attachments in Outlook and Gmail?
Word's mail merge can't attach files on Windows, where it also needs classic Outlook to send. Gmail's own mail merge sends one attachment to everyone. A different file for each person needs an add-in. Groupmail 7 sends the same files to everyone from your Microsoft 365, Outlook.com, Gmail or other email account, but it can't send a different file to each person.
The short answer
Checked 26 October 2026:
| Route | One file to everyone | A different file for each person | Notes |
|---|---|---|---|
| Groupmail 7 | Yes | No | From your Microsoft 365, Outlook.com, Gmail or other email account |
| Word with classic Outlook (Windows) | No | No | Microsoft: you can't add attachments |
| Word for Mac | Only the merged document | No | The email has no body text |
| New Outlook "Start mail merge" | Not documented by Microsoft | No | No names or other fields |
| Gmail's mail merge (paid Workspace editions) | Yes | No | Up to 1,500 recipients a day for mail merge |
| Gmail add-ons (GMass, Mailmeteor, YAMM) | Yes | Yes, with files from Google Drive | Gmail and Google Sheets |
Why Word's mail merge can't attach files
Microsoft's own instructions say you can't add attachments to a mail merge from Word on Windows. You can only include links. If you drag a PDF into the Word document, it goes in as an icon, not as an attachment, and nobody receives the file.
On Windows, Word's merge also sends through classic Outlook, so it doesn't work with the new Outlook. On a Mac, Word can send the merged document itself as the attachment, but then the email has no text of its own.
Send one file to everyone
This is the usual case for a price list, a brochure, an event programme or a form.
- Gmail: Gmail's own mail merge, in paid Google Workspace editions, includes your attachment in each person's copy.
- Outlook, Microsoft 365 or any address: in Groupmail 7, write the email, choose Attach file, and add
{{first_name}}where the name goes. Each person gets their own email with the file attached, from your address. It works whichever Outlook app you use, because Groupmail sends through your account, not through the app.
Send a different file to each person
For invoices, certificates or payslips, each person needs their own file. Groupmail 7 can't do that. Tools that can:
- For Gmail: GMass, Mailmeteor's Google Sheets add-on and YAMM can attach a different Google Drive file to each email, named in a column of your sheet.
- For Outlook: Outlook mail merge add-ins, or a Power Automate flow in Microsoft 365. Check that the one you choose supports the Outlook you use.
Some guides tell you to share each file as "Anyone with the link can view". Think twice before doing that with invoices or payslips: anyone who gets hold of the link can open the file.
Attachment size limits
- Microsoft 365: 35 MB per email by default; your organisation can change it.
- Gmail: 25 MB per email (up to 50 MB on Google Workspace Enterprise Plus, on the web). Larger files are sent as a Google Drive link.
- Groupmail 7 through Microsoft or Gmail sign-in: the whole email can be about 3 MB, so attachments can be a little over 2 MB.
- Groupmail 7 through SMTP2GO or your own mail server: up to 25 MB of files per email.
Every copy carries the file, so a 2 MB brochure sent to 1,000 people is 2 GB of email. For anything big, put the file on your website or in shared storage and send a link instead.
Questions people ask
Can I include an attachment in a mail merge email?
Not with Word's mail merge on Windows, which can only include links. On a Mac, Word can send only the merged document as the attachment. Gmail's own mail merge and Groupmail 7 can attach the same file to every email.
How do I mail merge with a different attachment for each person?
Use a tool that reads each person's file name from a column in your list, such as a Gmail add-on with Google Drive, or an Outlook add-in. Groupmail 7 can't send a different file to each person.
How do I send a mass email with an attachment in Outlook 365?
Word's mail merge on Windows can't attach files, and the new Outlook's "Start mail merge" can't add names. Groupmail 7 sends each person their own email with the same attachment from your Microsoft 365 address, with their name in it.
Can you do a mail merge with a PDF attachment?
Yes, if everyone gets the same PDF: attach it in Gmail's mail merge or in Groupmail 7. Through Microsoft or Gmail sign-in, Groupmail can send a PDF of a little over 2 MB; through SMTP2GO it can be bigger.
Can Gmail's mail merge send attachments?
Yes. In the Google Workspace editions that have mail merge, Gmail includes your attachment in each person's copy. Everyone gets the same file.
How do I send an attachment that's too big?
Put the file in shared storage or on your website and send a link. In Groupmail 7 you can also send through SMTP2GO or your own mail server, which allows up to 25 MB of files.
How many emails with attachments can I send a day?
Your email account sets the limit: Gmail's mail merge allows 1,500 recipients a day, and a Microsoft 365 mailbox 10,000. For newsletters and large marketing sends, use a sending service such as SMTP2GO rather than your mailbox.
Try Groupmail 7 free for 30 days.
No card needed. Then $599 once, with a 30-day money-back guarantee.