Central phone book
for Microsoft Teams

The phone book that Microsoft Teams is missing

Contact chaos vs. a single source

When no one knows which number is the right one

By default, Teams only shows each user their own contacts—no shared directory, no external numbers, and no useful search function. A central phone book turns all three of these aspects on their head: shared data, both internal and external contacts, and a search function that actually finds what you’re looking for.

Here's how Teams works by default
With prime Directory from partimus
Here's how it works

One source, available everywhere

prime Directory connects the systems where your contacts are already stored and consolidates them into a single, consistent database. Entra ID, Outlook mailboxes, CRM systems, and manually maintained sources are all consolidated in one place and automatically kept up to date—accessible in Teams, Outlook, and on mobile devices.

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Connect sources

Entra ID, Outlook mailboxes, CRM systems, and manually maintained lists are integrated. All relevant contact sources are consolidated in one place, rather than having to be searched individually.

Merge and synchronize

The sources are synchronized bidirectionally: Data is reconciled, duplicates are removed, and changes are kept up to date in both directions—without the need for manual maintenance.

Deploy everywhere

The completed contact list is available as a native tab in Microsoft Teams, Outlook, and on mobile devices. Your employees can access the same, up-to-date list from anywhere.

Try out prime Directory

Try it for 30 days with no obligation

The easiest way to see what prime Directory can do is to try it out in your own Teams. Test the central address book for 30 days with your real contacts—fully set up, with no obligation. If it doesn’t work for you, access ends automatically.

Functions at a glance

What prime Directory can do

From automatic data synchronization to one-click calling, prime Directory covers the entire process—from scattered contact information to a completed call. Every feature is designed to help your employees reach the right person faster—without switching tools, without searching for numbers, and without dealing with outdated data.

Bidirectional synchronization

Entra ID, Outlook, and CRM are synchronized and kept up to date in both directions. One change is all it takes—it takes effect everywhere.

Full-text search

You can search by name, company, department, or note—even by partial matches. Results appear immediately, even with very large contact databases.

Security and privacy

Contact information that remains protected

prime Directory works with the identities and permissions that are already in place in your Microsoft 365 environment. No parallel user accounts or separate password database are created—access is managed entirely through your existing Microsoft identities.

Entra ID native

Sign-in and permissions are handled through your Microsoft identities. No shadow users, no additional password management.

Modern authentication

Access is provided via OAuth 2.0 using short-lived tokens and automatic rotation—a current, validated standard.

End-to-end encryption

The data is encrypted using TLS 1.3 both during transmission and while stored. There are no plaintext paths.

GDPR-compliant

Data processing on behalf of third parties, data minimization, and the right to access and erasure are taken into account from the very beginning.

Optionally self-hosted

Depending on your preference, prime Directory can run in your own tenant or at the partimus data center in Limburg, Frankfurt, or Munich—with geographic redundancy and ISO 27001 certification. You decide where your contact data is stored.

Complete audit log

Every access and every change is logged in an audit-proof manner. This ensures that it is always possible to trace who viewed or edited what.

Pricing and packages

Three packages, with transparent pricing

prime Directory grows with your business. From a small team to a large corporation, you pay only for the features you actually need. All prices are per month, plus VAT, with a minimum term of 12 months and the option to cancel on a monthly basis thereafter.

Starter

For small teams of up to 25 people

€ 49 * per month

Business

For companies with up to 250 employees

€ 149 * per month

Recommended!

Enterprise

For corporations and critical industries

€ 399 * per month
Payment options

Monthly

|

Annually

Save 10%

|

3-year contract

Save 18%

Payment by invoice or SEPA direct debit

*All prices are monthly/non-recurring fees plus VAT. Our offer is aimed exclusively at business customers.

Cost-effectiveness

How much does it cost to find contacts?

Scattered contact information costs time above all else—every day, with every call. If you add up those seconds over the course of a year, what starts as a minor inconvenience turns into a significant amount of time. Consider a company with 50 employees, each making 5 calls per day, with 30 seconds spent searching for contact information per call, at an hourly rate of €40. Even these few seconds add up significantly over the course of a year.

550 h
Time saved per year

via Click-to-Call and full-text search

22,000 €
Savings in personnel costs

based on €40 per hour

over 1,000%
ROI in the First Year

with regard to the Business License

50 employees × 5 calls × 30 sec × 220 workdays ≈ 550 hours. 550 h × € 40 = € 22,000 in saved work time. Business license costs: € 149 × 12 = € 1,788. This results in an ROI of approximately 1,130%—and that’s not even accounting for the benefits of fewer misconnections, cleaner data, and faster onboarding.

To go with it

Find, call, be reachable—all in one place

prime Directory provides the contacts, and Teams Calling provides the connection. When you make a call from the central address book with a single click, you’re calling directly through Microsoft Teams—without a separate phone system. Together, they turn Teams into a complete communications hub: find contacts, make calls, and stay reachable—all in one place.

Call with a click, real connection

Click-to-Call from prime Directory uses Teams Calling to connect to the public telephone network.

One interface

Contacts, calls, chat, and presence are all integrated into Microsoft Teams—without having to switch between applications.

Managed from German data centers

Telephony and the phone book are provided by a partner and operated in the ISO 27001-certified partimus data centers in Limburg, Frankfurt, and Munich.

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Get to know partimus

Get started with partimus

Take the opportunity to optimize your IT infrastructure and drive your business forward – contact us today to find out more about the tailored benefits partimus can offer you.

FAQ - Frequently asked questions

Questions and answers about prime Directory

prime Directory is a central directory for Microsoft 365. It brings together contacts from Entra ID, Outlook, and CRM and makes them available as a native tab directly in Microsoft Teams—with click-to-call, live status, and search across all sources.

By default, Teams only shows users their own contacts. External numbers are missing, and the search function only finds exact matches for the beginning of names. Teams does not provide a shared, searchable directory for the entire company—and that’s exactly the gap that prime Directory fills.

Entra ID, Outlook mailboxes, CRM systems, and manually maintained lists. The sources are consolidated, duplicates are removed, and they are continuously synchronized so that everyone sees the same up-to-date information.

Yes. prime Directory is embedded as a native tab in Teams. Your employees can work in their familiar environment and don’t need to learn how to use an additional application. The directory is also available in Outlook and on mobile devices.

Access is provided via Entra ID and OAuth 2.0, and data is encrypted using TLS 1.3. Upon request, we can host prime Directory in one of our ISO 27001-certified data centers in Germany—in compliance with the GDPR and with a complete audit log.

Yes. You have a choice: run the system in your own Microsoft tenant or have it hosted in the partimus data center. That way, you decide for yourself where your contact data is stored.

Plans start at €49 per month for up to 25 users and go all the way up to the Enterprise plan, which includes an unlimited number of users and self-hosting. Billing is on a monthly basis, with discounts available for longer-term commitments.

Yes. You can try prime Directory for 30 days with no obligation using your real contacts—fully set up. If it’s not a good fit, your access will end automatically at no additional cost.

Contact us—we'd be happy to show you how prime Directory works with your own contacts.