Outlook keeps contacts in each person's own mailbox, so the supplier one of you saved last month isn't in anyone else's list. Microsoft gives you a few ways to share them, and which ones work depends on the version of Outlook your team uses. Here they are, with what each one can't do, then how to build one list from everyone's mail.
In classic Outlook for Windows, with a work account on Microsoft Exchange, you can share a contacts folder: select it in People, then Home > Share Contacts. Microsoft doesn't support that in Outlook on the web, and lists it as under investigation for new Outlook. For a list the whole company can use, an admin can set up a shared mailbox, or add outside contacts to the company address book. Anyone can export contacts to a CSV file and send it round, but that's a copy that starts going stale the day it's sent. Sigbot takes a different route: everyone connects their own Outlook, and on team plans you share folders, so the whole team works from one contact list built from everyone's mail.
| Shared contacts folder | Shared mailbox or address book | CSV file | Sigbot | |
|---|---|---|---|---|
| Who sets it up | Anyone, in classic Outlook | An admin | Anyone | Each person connects their own Outlook; you share folders (team plans) |
| Who's in it | The contacts one person saved | The contacts someone adds to it | A copy of one person's contacts | The people whose signatures are in your team's mailboxes |
| New Outlook and the web | Classic Outlook only | Mailbox contacts: classic Outlook only. Address book: all versions | Every version can import it | In the browser and the phone apps, whichever Outlook each person uses |
| Kept up to date | When its owner edits it | When someone edits it | No: send a new file | Checks everyone's mail by itself: daily on paid plans |
This lets colleagues open one of your contacts folders in their own Outlook, and you choose whether they can change it. It needs a work account on Microsoft Exchange, and works with people in your organisation; with people outside it only if your company's sharing policy allows.
What it doesn't cover. A shared folder holds the contacts its owner has saved, so it's only as complete as that one person's typing. The people your colleagues deal with are in their own mailboxes, and most of them were never saved as contacts at all: their details are in the signatures of the emails they've sent.
If your company uses Microsoft 365, whoever looks after it can set up a list for everyone. Microsoft documents two ways, and each has a catch.
Anyone can do these, in any version of Outlook, with no admin. What arrives is a copy, so it doesn't change when your contacts do.
Microsoft's own word for the export is a copy. When someone changes their number next month, nobody's file changes with it, and each person who edits their copy has a different list. To bring a fresh file into Outlook without duplicates, see how to keep your Outlook contacts up to date.
Sigbot reads the email signatures in Outlook and Microsoft 365 and turns each one into a contact: name, job title, company, phone, email and address. On team plans, everyone connects their own Outlook and you share folders, so the whole team works from one contact list built from everyone's mail, not from what one person remembered to save.
Start a team plan (Starter or Professional) at sigbot.app and invite your people.
Each person connects their own mailbox with their Microsoft account. The first scan reads the signatures already in it; newsletters and no-reply mail wait in a review queue.
Put contacts in team folders, by project, client or trade, and everyone works from the same list.
Whichever Outlook each person uses. Sigbot reads each mailbox through the person's Microsoft account, not through the Outlook app on their computer, so it's the same in classic Outlook, new Outlook or the web. The shared list is in Sigbot, in the browser at sigbot.app and in the iPhone and Android apps.
It keeps up by itself. After the first scan, Sigbot checks each connected mailbox for new mail: every day on paid plans, every week on Free. New people are added as they email any of you. Duplicates can be merged, and merges can be undone.
On everyone's phone. Caller ID sync in the phone apps can add team folders to each person's address book, so calls from the people the whole team deals with show a name and company: caller ID from your Outlook contacts.
In Excel or Outlook when you need it. Export the whole list, a folder or a selection to Excel or CSV. Sigbot only reads mail and doesn't write to anyone's Outlook contacts, so to have the list in Outlook too, import the CSV as above.
At work, IT approves it once. Microsoft's default setting stops people giving any outside app access to their mail, so most companies have an admin approve Sigbot once, for everyone. Sigbot's Outlook app is publisher-verified by Microsoft (SIGBOT LTD). Our one-page brief for IT admins has the approval link.
Every Outlook and Microsoft 365 step above was checked against Microsoft's support and Learn pages on 26 October 2026. Microsoft changes its menus, and adds features to new Outlook, from time to time; if yours look different, these pages have the latest.
Outlook, Microsoft 365, Exchange and PowerShell are trademarks of the Microsoft group of companies.