There are three different “groups” in Outlook and they behave differently when you email them. Picking the right one matters because they have different limits, different visibility, and different reply behavior.

This guide walks through each method, when to use it, and the gotchas that catch people off guard.

---

What “Group” Means in Outlook

Outlook uses the word “group” for three completely different things:

Type	Where it lives	Best for
Contact group (a.k.a. personal distribution list)	Your contacts only — no one else sees it	Personal use, small groups
Distribution list	Microsoft 365 admin / Exchange directory	Org-wide email lists
Microsoft 365 group	Microsoft 365, with shared inbox + calendar	Team collaboration

If you just want to email the same 12 people every Friday, a contact group is fine. If you want everyone in marketing to get the same email and have an admin manage the membership, that’s a distribution list. If you want a shared mailbox, calendar, and OneDrive folder for a project team, that’s a Microsoft 365 group.

---

1. Send to a Contact Group (Personal)

A contact group lives in your personal contacts. No one else can use it. When you send to it, Outlook expands the group into individual recipient addresses on your end.

If you don’t have a group yet

See How to create a distribution list in Outlook for the setup steps. Once it exists, come back here.

Send to the group

Classic Outlook for Windows:

1. Click New Email.
2. In the To field, start typing the contact group name. Outlook auto-completes it (the group name shows in bold to distinguish it from individual contacts).
3. Press Enter or Tab to confirm.
4. (Optional) Click the + next to the group name to expand it into individual recipients before sending. Once expanded, you can remove specific people. Warning: expanding can’t be undone — you’ll need to retype the group name to collapse it.
5. Add a subject and body.
6. Click Send.

New Outlook & Outlook on the web:

1. Click New mail.
2. Type the contact group name in To. The group icon appears next to the name.
3. Pick it from the auto-complete dropdown.
4. Add the message and click Send.

Outlook for Mac:

1. Click New Email.
2. Type the contact group name in To.
3. Pick it from the auto-complete list.
4. Send.

Reply behavior

When recipients hit Reply, the reply only goes to you (not the rest of the group). When they hit Reply All, the reply goes to everyone the original was sent to as individuals — the contact group itself is just a label.

---

2. Send to a Microsoft 365 Group

A Microsoft 365 group has its own email address (something like marketing@yourcompany.com). When you send to it:

• The message goes to everyone currently in the group
• A copy is archived in the group’s shared inbox
• New members joining later can read the archived message
• Reply All to a group message goes back to the group, not individual members

Send to a Microsoft 365 group

All Outlook versions:

1. Click New Email / New mail.
2. Type the group’s email alias in the To field (e.g., marketing@yourcompany.com).
3. Or, in the new Outlook and web, click the Groups section in the left navigation, pick the group, and click New conversation or Email group.
4. Add a subject and body.
5. Click Send.

See what groups you’re a member of

New Outlook & web: Click the Groups section in the left navigation. Every group you belong to is listed.

Classic Outlook: Expand the Groups section in the navigation pane (left side, under your inbox). Click any group to see its conversations and member list.

If the Groups section isn’t visible, your account isn’t on Exchange / Microsoft 365 (POP3 and IMAP accounts don’t support Groups).

Send vs. post in a Microsoft 365 group

There are two ways messages get into a Microsoft 365 group:

• Email it — anyone (including external senders if allowed) sends to the group address.
• Post a conversation — go into the group inside Outlook, click New conversation, and write a message that lands in the shared inbox without going through email.

Both end up in the same place. Use email when you want non-members to be able to send too.

---

3. Send to a Distribution List (Exchange Directory)

A distribution list (DL) is an admin-managed mailing list in your org’s directory. You don’t create or manage it — IT does. To send to one, you just need its email address.

1. Click New Email.
2. Type the DL name or address in To (e.g., all-engineering@yourcompany.com).
3. Outlook auto-completes from the global address book.
4. Add subject and body.
5. Click Send.

Find a distribution list

Classic Outlook:

1. Click New Email.
2. Click the To button to open the address book.
3. In the Address Book dropdown, pick Global Address List.
4. Browse or search for the DL name.

New Outlook & web: Type the DL name in the To field — auto-complete pulls from the directory. To browse, click the People icon in the left navigation and search.

Reply behavior

Replies to a DL go back to the DL (everyone on it). To reply only to the sender, use Reply instead of Reply All — but note that DLs sometimes have reply-to set to the DL address, so even Reply can hit the whole list. Check before pressing send.

---

4. Send to a Group via BCC (Hide Recipients from Each Other)

If you’re emailing a group of people who don’t know each other — clients, prospects, alumni — put the group in BCC so each recipient can’t see the others.

Add BCC to your email

If the BCC field isn’t visible:

• Classic Outlook: Click Options in the new email window, then Bcc.
• New Outlook & web: Click Bcc in the top right of the compose window (next to the To field).
• Outlook for Mac: Click Options > Bcc.
• Mobile: Tap the down-arrow next to the To field to expand Cc and Bcc.

For more on BCC, see How to BCC in Outlook.

Send

1. Put your own address in To (or leave it blank — Outlook will use your address by default for sent mail).
2. Put the group name or list of recipients in Bcc.
3. Add subject and body.
4. Click Send.

Each recipient sees only their own address in the To field. They cannot see anyone else who got the email.

---

5. Send Personalized Email to a Group (Mail Merge)

If you want each recipient to get a slightly different version — “Hi [First Name]” or with different attachment names — use Word mail merge instead of sending a single bulk message.

Mail merge from Outlook contacts

1. Open Word (not Outlook).
2. Go to the Mailings tab.
3. Click Start Mail Merge > E-mail Messages.
4. Click Select Recipients > Choose from Outlook Contacts.
5. Pick the contacts folder or group you want to use.
6. Write your email, inserting Merge Fields (First Name, Company, etc.) wherever you want personalization.
7. Click Finish & Merge > Send Email Messages.
8. Set the To dropdown to the field with email addresses, the Subject Line, and the Mail Format (HTML).
9. Click OK.

Word generates one personalized email per contact and pushes them to your Outlook outbox.

Mail merge limits

Microsoft 365 work and school accounts (Exchange Online) cap you at roughly 30 messages per minute, 500 recipients per message, and 10,000 recipients per day. Personal Outlook.com accounts are much tighter — around 300 recipients per day and 100 recipients per message. For larger sends, use a real email service (Mailchimp, Customer.io, SendGrid, etc.).

---

6. Outlook Mobile

Sending to a contact group on mobile works only if the group already exists in your account contacts.

1. Open the Outlook app.
2. Tap New email (the pencil icon).
3. In the To field, start typing the group name. Mobile auto-complete pulls from your synced contacts.
4. Pick the group.
5. Compose and send.

Microsoft 365 groups also auto-complete by their email alias. Mail merge isn’t supported on mobile.

---

7. Common Problems

The group doesn’t show up in auto-complete.

• For contact groups: confirm the group is saved in People (not just the auto-complete cache). Open Contacts, search for the group name. If it isn’t there, recreate it.
• For distribution lists: confirm you’re connected to the directory. POP3 and IMAP accounts don’t see global address lists.
• For Microsoft 365 groups: confirm you’re a member of the group, or that the group is set to public so non-members can find it.

Recipients say they didn’t get the message.

• The message may have hit a spam filter on their end (especially if you sent to a large BCC list — looks like spam to filters).
• You may have hit the daily send limit. Check your Outbox — if messages are stuck there, you’ve been rate-limited.
• The contact group expanded only some addresses if any were broken. Open the Sent copy and check the To/Bcc lines.

Reply All is blowing up the group.

• Set reply-to at the DL or M365 group level (admin task) to a single moderator address, so replies don’t go to everyone.
• For one-off sends, ask recipients in the body of the email to reply only to you, not all. Better still, use BCC.

I sent to a 200-person BCC list and Outlook crashed.

• Outlook can be slow on very large BCC sends. Break it into batches of 50–100 recipients, or use mail merge so each recipient gets a separate message.

---

Quick Reference

Method	Visible recipients	Personalized	Reply-all hits	Best for
Contact group in To	Each member	No	Each member individually	Personal small groups
Microsoft 365 group	Group address only	No	The group	Team collaboration
Distribution list	DL address (or expanded)	No	DL or sender	Org-wide announcements
BCC	Hidden	No	Sender only	External lists, privacy
Mail merge	Each member sees only themselves	Yes	Sender only	Personalized outreach

---

Stop Sending the Same Email Over and Over

If you’re emailing the same group with similar messages on a regular cadence — weekly updates, client check-ins, follow-ups — Carly can draft, personalize, and send those for you. It connects to Outlook plus 200+ other apps and handles the repetitive parts of your inbox.

More on Outlook: How to create a distribution list · How to BCC in Outlook · How to create an email template · How to schedule an email · How to import contacts into Outlook

Related Articles

Guides

How to Create a Distribution List in Outlook (2026 Guide)

Mar 27, 2026

Guides

How to Create a Poll in Outlook (Every Version, 2026)

Apr 3, 2026

Guides

How to Create a Shared Mailbox in Outlook (2026 Guide)

Apr 3, 2026