Shared mailboxes, distribution lists and Microsoft 365 groups: which to use for info@ and sales@

Almost every small business has a few addresses that do not belong to one person: info@, sales@, billing@, support@. In many offices those addresses are set up as a regular user account with a shared password, or as an alias on the owner's mailbox. Both approaches cause trouble sooner or later.

Microsoft 365 offers three better options: shared mailboxes, distribution lists and Microsoft 365 groups. They look similar from the outside but behave very differently. Here is how to pick the right one.

Why not just share a login

A user account with a password everyone knows is hard to secure. You cannot easily use MFA when five people share one phone number, you cannot tell who sent what, and every time someone leaves you have to change the password and update every device. It also uses a paid license that may not be needed.

Shared mailbox: one inbox, many people

A shared mailbox is a mailbox with its own address that several people can open from their own accounts. Nobody signs in to it directly. You grant permissions, and it appears in each person's Outlook alongside their own inbox.

• Everyone sees the same messages, folders and sent items.
• When one person replies or files a message, others can see it was handled.
• Replies can come from the shared address instead of the person's own address, with "Send As" permission.
• It has its own calendar and contacts.
• Small shared mailboxes generally do not need their own license, but large ones, archiving and some compliance features do. Check current Microsoft licensing for your situation.

Best for: info@, billing@, support@ and any address where a small team handles incoming requests and needs to see what has been answered.

Distribution list: one address, many copies

A distribution list, also called a distribution group, is just an address that forwards a copy of every message to each member. There is no shared inbox. Each person gets their own copy in their own mailbox.

• Simple to set up and easy for staff to understand.
• Nobody can see whether someone else already replied.
• Replies go out from each person's own address unless extra permissions are set.
• Useful for internal announcements, such as an allstaff@ address.

Best for: announcements and notifications where everyone should get the message but nobody needs to coordinate a reply.

Microsoft 365 group: inbox plus files and calendar

A Microsoft 365 group gives a set of people a shared conversation inbox along with a shared calendar, a SharePoint file library and a planner. When you create a team in Microsoft Teams, a Microsoft 365 group is created behind it.

• Members can read group conversations in Outlook, and can choose to get copies in their own inbox.
• It works more like a discussion thread than a traditional inbox.
• It comes with shared files and a calendar for the group.
• It can accept mail from outside the company if you allow it.

Best for: project teams or departments that collaborate across email, files and meetings. It is usually less suited to a busy customer-facing inbox, where a shared mailbox gives clearer tracking.

A quick way to choose

1. Does a small team answer messages sent to this address? Use a shared mailbox.
2. Does everyone just need a copy, with no shared tracking? Use a distribution list.
3. Does the group also share files, a calendar and a Teams space? Use a Microsoft 365 group.

For a typical small office, that often means a shared mailbox for info@ and billing@, a shared mailbox or group for sales@ depending on how the team works, and a distribution list for allstaff@.

Setup tips that save headaches

• Block direct sign-in for shared mailboxes, so the mailbox can only be reached through permissions.
• Grant access to security groups rather than individual people, so new hires get access automatically.
• Decide whether sent items from a shared mailbox are saved in the shared mailbox, so everyone can see replies.
• Limit who outside the company can email internal distribution lists, to reduce spam and phishing.
• When an employee leaves, consider converting their mailbox to a shared mailbox so a manager can keep handling incoming mail. Our employee offboarding IT checklist covers this step.

Getting help

If your info@ address is still a shared login, or you are not sure what you have set up today, our Microsoft 365 team can review it and move each address to the right type without losing mail. We work with offices across Los Angeles County, the Inland Empire and Ventura County, and can also tighten email security while we are in there.