PSTN Calling

Connect your employees wherever they are with all new calling capabilities in Skype for Business. Use one convenient tool to manage your business calls with flexible, comprehensive plans for local, long distance, and international calling.

Now you can add PSTN Calling to your Office 365 Enterprise E5 subscription.
Learn more about Office 365 Enterprise E5

Fast, flexible provisioning

Keep the phone numbers you already have, or easily request and assign new numbers in minutes for employees in multiple locations—no new lines or equipment needed.

Reliable inbound calling

Receive calls using Skype for Business IP phones, PCs, and mobile devices wherever you are. Easily manage calls with features like hold, forward, transfer, and voicemail.

Worldwide outbound calling

Use your Skype for Business client to make outbound calls to any phone number—domestic or international. In case of emergencies, use the built-in emergency dialing.

PSTN Calling includes:

Number portability

Use your existing phone numbers with local number porting built-in. Take advantage of automated online processing, or contact our team for help with large porting requests.

Easy automation

Automate the management of your PSTN service using Windows PowerShell. Get new numbers from across the globe, and assign them to users in a completely automated process.

Integrated number reservation

Reserve numbers in major cities around the country and in nearly every area code. Allocating Direct Inward Dial (DID) numbers for users is included in the service.

Office 365 management

Optimize your operations using the Office 365 administrative suite. Use one convenient tool to manage all your communication and collaboration capabilities.

Reliable operations

With emergency dialing built in, you get reliable connectivity based in the cloud and seamless integration with Office 365.

Requirements for PSTN CallingTooltip with information about PSTN calling

Table show details of PTSN Calling plans
 Office 365 Enterprise plans and information on pricing for PSTN calling
Calling Plan Price Tooltip with details about quantity of domestic and international minutes
Total Price Tooltip with details about taxes and usage limits

Office 365 Enterprise E5

product features and pricing information
No additional requirements

Domestic: {PSTNBizE5Domestic|price}

International: {PSTNBizE5International|price}

Domestic: {PSTNBizE5Domestic|price}

International: {PSTNBizE5International|price}

Office 365 Enterprise E3

product features and pricing information
Cloud PBX ({CloudPBXO365E3|price})

Domestic: {PSTNBizE3Domestic|price}

International: {PSTNBizE3International|price}

Domestic: {PSTNBizE3TotalDomestic|price}

International: {PSTNBizE3TotalInternational|price}

Office 365 Enterprise E1

product features and pricing information
Cloud PBX ({CloudPBXO365E1|price})

Domestic: {PSTNBizE1Domestic|price}

International: {PSTNBizE1International|price}

Domestic: {PSTNBizE1TotalDomestic|price}

International: {PSTNBizE1TotalInternational|price}


See rates for where you want to call.

Consumption rates outside of baseline rates Tooltip with details about taxes, international rates, and rate changes

Download PDF


Show all

PSTN Calling provides domestic and international calling plans with Skype for Business. Organizations can subscribe to calling plans from Office 365 and use existing phone numbers or get new numbers.

For additional information, see What is PSTN calling?

Yes, customers with Enterprise E1 and E3 can upgrade to PSTN Conferencing and Cloud PBX + PSTN Calling as standalone offers.

While Cloud PBX provides the call control capabilities for end users and the administrative features for IT, it connects to the PSTN through either Microsoft PSTN Calling add-on or to your existing PSTN circuits using Cloud Connectivity.

Yes, in order to use these services, you must have Skype for Business Plan 2, or equivalent E SKU (E1/E3/E4/E5), deployed as a standalone or as a component of Office 365 Enterprise E1, E3, or E5 suites. To use PSTN Calling, you must also purchase Cloud PBX or Office 365 Enterprise E5 (which includes Cloud PBX functionality) as a prerequisite.

If you are an Office 365 Enterprise E5 or Cloud PBX customer, you can connect your existing PSTN service provider with Microsoft cloud-based call control. Scenarios are based on whether a customer already has a Skype for Business Server deployed. You can set up a new server pool or use an existing Skype for Business Server deployment to configure it to connect to Cloud PBX functionality that is covered under existing server licensing.

If you don’t have an existing server, you can use a minimal Skype for Business Server deployment through the Cloud Connected Edition that includes four preconfigured Virtual Machines (VMs) deployed on customer-owned Windows Servers. Skype for Business Server roles in VMs are not paid roles and are licensed for use with Cloud PBX.

PSTN Calling is subject to geographical and channel availability. Initial availability of PSTN Calling for the United States was on December 1, 2015. See International availability for more information.

  • For domestic PSTN Calling plans, each licensed user is allocated the above-stated domestic dial-out minutes pooled at the tenant level.
  • For international PSTN Calling plans, each licensed user is allocated the above-stated domestic dial-out minutes and 600 international dial-out outbound minutes pooled at the tenant level.

For all local and international calls placed to users within the same tenant, peer-to-peer calling is enabled and the call is placed over the Voice Over IP network, meaning that all local and international calls placed within the tenant will not count towards the allocated minutes.

If you are set up for PSTN Consumption billing, when you exceed the PSTN Calling allocated minutes (the total of all minutes associated with users’ assigned licenses pooled at the tenant-level), you will be charged for usage that goes above and beyond the tenant-pooled limits. If you are not set up for Consumption billing, you will lose your service until the minute limits are reset the following month.

No, domestic and international minute allocations are based on a monthly cycle. Any minutes that are unused during one month will not rollover to the next month.

Calls placed to other users whose license resides in the same Office 365 tenant, domestic or international, will not count towards the excessive use limits for PSTN Calling. When calls are placed within the same tenant, reverse number lookup functionality will validate that the call originated in the same tenant, and it will be placed as a peer-to-peer call on the Voice Over IP network, if available.

Domestic calling, per the Skype for Business Online PSTN service use terms, is defined as: “The ability for the user to make calls to numbers located within the country of Office 365 assignment for that user.” In other words, if a US-based user (meaning their Office 365 license is assigned in the US) travels to London, any calls they make back to the US are considered domestic calls.

Consumption billing for PSTN services will launch on June 1, 2016, enabling PSTN Conferencing toll-free dial-in, international dialing for users with PSTN domestic calling, and additional domestic and international calling minutes.

Set-up and management:

  • Customer selects an individual pre-paid balance amount (e.g. $100), minimum balance threshold (e.g. $10), and balance replenishment amounts (e.g. $90).
  • Customer funds their pre-paid balance directly in the Office 365 Portal (as opposed to buying on CPS – SKU on PL).
  • It’s important to establish appropriate replenishment amounts as all payments made to fund prepaid balance are valid for one year.
  • If customer elects to not set up a pre-paid balance and they reach their monthly excessive usage limit, their PSTN services is suspended for the remainder of the month.

Payment model:

  • Account balance is drawn down as services are consumed.
  • Customer can select their EA Enrollment as a payment instrument in the Office 365 Portal.
  • Each time a customer’s balance reaches the minimum threshold, a replenishment of funds is triggered at which time the customer is invoiced.

Billing and reporting:

  • Consumption billing charges appear as a line item on the EA Invoice as Skype for Business PSTN Consumption.
  • Usage reports are available in the Admin Center at any time.
  • Customers without an EA can set up an account with a credit card or invoicing payment model.

Yes. Usage reporting will be available via the Skype for Business Admin Center.

In addition, you can restrict usage to certain users if they are at risk of exceeding their monthly tenant-pooled limits.

Yes, you can assign users phone numbers directly through the Skype for Business Admin Center. For more information, see Getting phone numbers for your users. If your users already have phone numbers assigned by another provider, you can transfer those existing phone numbers from your service provider or phone carrier.

You can also add up to 10 percent more numbers in addition to what you have licenses for. For example, if you purchase 100 licenses, you can acquire up to 110 new telephone numbers.

Note: the above applies only to acquiring NEW phone numbers through Office 365 and Skype for Business; there is no limit on porting in telephone numbers to our service; if you own the telephone number, you can port in any quantity of telephone numbers regardless of the number of licenses you have.

Yes, there will be a self-service form on the Office 365 Admin portal. Customers who have more than 150 users can engage with a FastTrack engineer to assist with the process.

For additional information, see Transfer phone numbers over to Skype for Business Online.

Yes, you can make and receive phone calls using Skype for Business IP phones, PCs, and mobile devices. For additional information, see Supported phones for Skype for Business Online.

If you have PSTN Consumption billing enabled, you can pay per minute for international calls. Otherwise, the international call will not connect.