Mail Merge in New Outlook: Does It Work? How to Do It (2026)

Word mail merge doesn't work in New Outlook. Here's why, what New Outlook's built-in mail merge can do, and how to send personalized emails from Excel.

Updated September 2026

Can it send a personalized mail merge from a spreadsheet in New Outlook?

Option	1 Classic Word Merge	2 New Outlook Merge	3 SecureMailMerge
Can it send a personalized mail merge from a spreadsheet in New Outlook?	No	Not yet	Yes
What each route can do once set up
Fields from Excel or CSV	Yes, via Word	No, same text for all	Yes, any column
Runs in New Outlook	No	Yes	Yes
Mac and web	Limited, no	No, yes	Yes, yes
Preview each email	Partly, in Word	No	Yes
Attachment per recipient	No	Same file to all	A different file per row
CC or BCC per recipient	No	No	Yes
Schedule or pace sending	No	No	Day, hours, daily cap
Sent mail appears as	One per recipient	One item, many recipients	One per recipient
Cost	In Microsoft 365	In Microsoft 365	Free with a promotional footer
How to set it up			Show me how to use SecureMailMerge

1. Classic Word Merge No Show me how to use Classic Word Merge

1. Classic Word Merge

Best for a one-off, on Windows only

Fields from Excel or CSV: Yes, via Word
Runs in New Outlook: No
Mac and web: Limited, no
Preview each email: Partly, in Word
Attachment per recipient: No
CC or BCC per recipient: No
Schedule or pace sending: No
Sent mail appears as: One per recipient
Cost: In Microsoft 365

Turn off the New Outlook toggle, top right.
Set classic as default: Windows Settings, Apps, Default apps, search "Outlook (classic)", set it for MAILTO.
Run Mailings, Finish & Merge, Send Email Messages.
Leave classic open until the Outbox empties.

Microsoft supports classic Outlook until at least 2029, so this keeps working for now. It is still not a long-term plan: since April 2026 New Outlook is what most people get by default, your organization can remove the toggle with at least 12 months' notice from Microsoft, and Mac and web users cannot do this at all.

2. New Outlook Merge Not yet Show me how to use New Outlook Merge

2. New Outlook Merge

Best for one identical announcement, sent privately

Fields from Excel or CSV: No, same text for all
Runs in New Outlook: Yes
Mac and web: No, yes
Preview each email: No
Attachment per recipient: Same file to all
CC or BCC per recipient: No
Schedule or pace sending: No
Sent mail appears as: One item, many recipients
Cost: In Microsoft 365

New message, Options tab, Start mail merge, or the arrow beside Send. Everyone gets their own copy, so nobody sees the other addresses.

It cannot read a spreadsheet, so personalization is not possible and attachments are the same file for everyone. Microsoft has announced a per-recipient version targeted for September 2026, still listed as in development on the Microsoft 365 roadmap.

3. SecureMailMerge Yes Show me how to use SecureMailMerge

What SecureMailMerge can do

Best for personalized mail merges from a spreadsheet, in any Outlook

Fields from Excel or CSV: Yes, any column
Runs in New Outlook: Yes
Mac and web: Yes, yes
Preview each email: Yes
Attachment per recipient: A different file per row
CC or BCC per recipient: Yes
Schedule or pace sending: Day, hours, daily cap
Sent mail appears as: One per recipient
Cost: Free with a promotional footer

Try SecureMailMerge in New Outlook Free version with a promotional footer. No credit card.

Why classic Word mail merge stops working

New Outlook cannot accept the messages Word’s merge hands over, so Word has nowhere to deliver them. Microsoft treats this as expected behaviour rather than a bug: there is no fix coming, and nothing on your side to repair. Microsoft’s own New and classic Outlook feature comparison (14 April 2026) lists mail merge as “Partially available” in New Outlook.

What happened to your emails depends on what is installed:

Classic Outlook is installed too: Word handed the merge to it instead. Open classic Outlook and check the Outbox, because the messages usually queue there.
Only New Outlook: nothing was sent. The merge completes in Word, no error appears, and no message leaves your computer.
On a Mac: Word can still merge, but only through Outlook for Mac set as the default mail app, with no preview, and with the Excel file closed. Many people report nothing sending at all.

The technical nitty gritty

Word’s email merge hands each message to Outlook through MAPI, a Windows messaging interface that only classic Outlook implements. New Outlook is built on the same architecture as Outlook on the web, which has no MAPI layer at all, so the hand-off has no destination. Microsoft’s own support engineers describe this as expected behaviour rather than a defect.

How to send a mail merge from Excel in New Outlook

SecureMailMerge is an add-in from Microsoft AppSource, published by Sol Inventum OÜ, the mail merge expert for Outlook 365. It adds a mail merge panel to the compose window, reads your Excel or CSV, and sends one email per row from your own mailbox. Nothing to install on the PC, nothing to set up in Word, and the add-in is identical in classic, New Outlook, Mac and web. Your spreadsheet, attachments and message content stay in Outlook and Microsoft 365, and are never sent to SecureMailMerge’s servers.

Seven steps. None of them involves Word.

Install SecureMailMerge from Microsoft AppSource. In New Outlook, open Apps in the left sidebar, search for SecureMailMerge, and choose Add. If your organization restricts add-ins, an administrator can deploy it for everyone from the Microsoft 365 admin center, using Microsoft’s own steps.
Prepare your spreadsheet. One row per recipient, one column holding the email addresses, and a column for anything you want to personalize, such as first name, company or invoice number. Excel and CSV both work.
Start a new email and open the add-in. Click the SecureMailMerge icon in the compose window toolbar, or find SecureMailMerge under Apps there.
Load your recipients. Upload the spreadsheet, then tell the add-in which column holds the email addresses.
Write your message and insert the fields. Choose a column from the dropdown to place that field in the subject or body, where it appears as {{FirstName}} and each recipient sees their own value. Set a default for any column that has empty cells.
Send yourself a test, then preview the mail merge. The preview shows each finished email with real values, so you can check the merge before anyone receives it.
Start the mail merge. The add-in calls it a campaign on screen. It generates the messages in your mailbox and sends them from your own address, one per recipient, with copies in your Sent Items.

Frequently asked questions

Mail merge in New Outlook

Does mail merge work with New Outlook?

Not the classic Word mail merge. New Outlook cannot accept the messages Word hands over, so Finish & Merge, Send Email Messages either opens classic Outlook or sends nothing at all. New Outlook has a built-in mail merge that sends one identical copy per recipient, and the SecureMailMerge add-in adds personalized mail merge from Excel.

Why does Word say it sent the emails but nothing arrives?

Word handed them to a mail client that is not there. If classic Outlook is installed, check its Outbox, because the messages usually queue there. If it is not installed, nothing was sent and no error was shown.

Can I still use Word mail merge if I switch back to classic Outlook?

Yes, on Windows, as long as classic Outlook is installed and set as your default mail app. Microsoft supports classic Outlook until at least 2029, but organizations can disable the switch back, and it is not an option on Mac or the web.

Is Microsoft adding real mail merge to New Outlook?

Microsoft's roadmap lists "Mail Merge (Advanced)" for Outlook on the web and New Outlook, adding per-recipient fields, targeted for September 2026. As of 8 September 2026 it is still listed as in development on roadmap item 423047, and data sources, attachments and preview are not documented. This page will be updated when it ships.

How many emails can I send in a day?

The limits are Microsoft's and apply whichever method you use. Work and school mailboxes allow up to 10,000 recipients per rolling 24 hours, and Outlook.com accounts fewer. SecureMailMerge can cap the daily total and spread sending over several hours to stay under. Sending limits explained.

If you use SecureMailMerge

How do I do a mail merge in New Outlook from Excel?

With SecureMailMerge, the only one of the three routes that reads a spreadsheet. Install it from Apps, open a new email, upload your Excel or CSV file, insert fields such as {{FirstName}}, send a test, preview, then start the mail merge. Each row becomes its own email, sent from your own mailbox.

Does SecureMailMerge work in Outlook on the web and on Mac too?

Yes. SecureMailMerge is the same add-in in classic Outlook, New Outlook, Outlook on the web and Outlook for Mac.

Do my existing Word mail merge templates carry over?

Not automatically. SecureMailMerge reads your spreadsheet, not the Word document, so paste the letter text into the Outlook compose window and re-insert the fields from the dropdown. For a typical letter this takes a few minutes.

Does my administrator have to approve SecureMailMerge?

In some organizations, yes. SecureMailMerge asks to read your contacts, create drafts while it uploads attachments, and send mail as you, and some tenants require an administrator to approve that once before anyone can use it. What each permission does.

Can I send different attachments to each person?

Yes. In SecureMailMerge, add an Attachments column naming the file for each row, and the add-in asks you to upload the files. Individual attachments guide.

Can I send from a shared mailbox?

Yes. In SecureMailMerge, run the merge from your own mailbox and switch the From address to the shared one, which your administrator grants with Send As. Replies go to the shared mailbox, though your copies land in your own Sent Items. Shared mailbox details.

Can I schedule the emails to send later?

Yes. SecureMailMerge generates the mail merge into your Drafts folder and sends on the day and during the hours you choose. Scheduling a mail merge.

SecureMailMerge: security, privacy and cost

Does my spreadsheet get uploaded anywhere?

No. SecureMailMerge processes recipient lists, spreadsheets, attachments and message content inside the add-in and sends through your own Microsoft 365 mailbox. Only your sign-in identity reaches SecureMailMerge's licensing service, for the license check. IT security documentation.

Does using SecureMailMerge change anything for my IT team?

No. These are ordinary emails sent from your own mailbox, so your organization's existing retention, archiving and audit rules keep applying exactly as they did before.

Is SecureMailMerge free?

Installing costs nothing. The free version includes every feature and adds a short promotional footer to each email. A license, sold as a per-user subscription, removes the footer. See pricing.

Mail Merge in New Outlook: Does It Work?