Your phone can only put a name to a number that's in its own contacts. When someone who has emailed you rings, their number is in their email signature, not your phone, so all you see is the number. There are three ways to fix that, from one caller at a time to everyone who has ever emailed you.
The Outlook app on your phone can copy your Outlook contacts into the phone's contacts, so they show by name when they call: it's Save Contacts on iPhone and Sync Contacts on Android. That only covers the people saved in Outlook, and at work your company can switch it off. Most people who email you were never saved, so their numbers are only in their signatures. Sigbot reads those signatures and puts the people on your phone, or on iPhone labels their calls without adding anything to your contacts.
| Outlook's setting | Save the caller | Sigbot | |
|---|---|---|---|
| Who shows by name | The contacts saved in Outlook | The callers you save, after they've rung | The people whose signatures are in your mailbox, or a folder you pick |
| Kept up to date | Yes, from Outlook | Only when you edit them | Yes, from Sigbot, which checks your mail for new signatures |
| At work | Your company can turn it off | Always works | Most companies have IT approve Sigbot once, for everyone |
If you use the Outlook app on your phone, this copies your Outlook contacts into the phone's own contacts, where caller ID looks for them.
What it doesn't cover. It copies your Outlook contacts: the people saved in Outlook. Someone who has only emailed you isn't an Outlook contact until you save them, so their number stays in their signature and your phone still shows just the number.
On iPhone the copy goes one way, so Microsoft says to edit these contacts in Outlook, not in the iPhone's Contacts app. On Android it goes both ways.
Once an unknown number has called, you can save it from your call list in a few taps. Look up who it was in your email first, and copy their name and company from the signature.
That fixes the second call, not the first, and one person at a time. On iPhone, Apple's Mail app can also suggest new contacts from the mail you receive, which you add one at a time; that doesn't apply to mail you read in the Outlook app.
Sigbot reads the email signatures in Outlook and Microsoft 365 and turns each one into a contact, phone numbers included. Its iPhone and Android apps then put those people on your phone, so the first call from someone who has only ever emailed you already shows their name and company.
Start free and connect Outlook. The first scan reads the signatures in your mailbox and files each person as a contact.
Install Sigbot from the App Store or Google Play and log in with the same account.
Open Profile > Caller ID & phone sync. Choose all your contacts or one folder, plus any team folders, and switch it on.
It keeps up by itself. After the first scan, Sigbot checks your mailbox for new mail: every day on paid plans, every week on Free. New people are added as they email you, and Caller ID picks them up on your phone.
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.
For a team: on team plans you share folders, so everyone's phone can show the callers the whole team deals with, not just the ones in their own inbox.
Every Outlook, iPhone and Android step above was checked against these pages on 25 October 2026. Menus change from time to time; if yours look different, these pages have the latest steps.
Outlook, Microsoft 365 and Intune are trademarks of the Microsoft group of companies. iPhone and iCloud are trademarks of Apple Inc. Android and Google Play are trademarks of Google LLC.