Teams Phone System Enterprise Guide 2026 | EPC

Microsoft Teams Phone System Guide 2026

Microsoft Teams Phone System is the voice platform built into Microsoft Teams. It replaces traditional PBX hardware with cloud-based calling solutions.

• Direct Routing
• Calling Plans
• Operator Connect

EPC Group is a Microsoft consulting firm with 29 years of experience. We have successfully migrated over 200 enterprises from PBX to Teams Phone.

Last updated: 2026 · Read time: ~12 min

Key facts

• Three PSTN connectivity options: Direct Routing (your carrier via SBC), Calling Plans (Microsoft as carrier), Operator Connect (certified carrier partners in the Teams admin center).
• Teams Phone System license required — included in Microsoft 365 E5; available as add-on for other plans.
• Auto-attendants and call queues replace legacy IVR and ACD systems.
• Compliance recording is supported through certified partners (NICE, Verint, ASC Technologies).
• Dynamic E911/E112 routes emergency calls to the correct local PSAP based on user network location.
• EPC Group has delivered Teams Phone migrations for 200+ enterprise organizations across multiple countries.

PSTN connectivity options

The connectivity decision is crucial for a Teams Phone deployment. Making the wrong choice can lead to two major issues:

• Overspending on carrier costs.
• Under-delivering on geographic coverage.

Direct Routing

Direct Routing connects Teams Phone to your carrier using a Session Border Controller (SBC). You keep your current carrier contracts. You keep your existing phone numbers.

This option offers full control over carrier selection, pricing, and coverage. It is perfect for enterprises that:

• Have existing carrier relationships
• Operate in multiple countries
• Are in areas where Microsoft Calling Plans are not available

Microsoft Calling Plans

Microsoft is the carrier. You buy domestic or international calling minutes directly from Microsoft. No SBC is required. This is the simplest option technically.

It is best for smaller deployments and regions where Microsoft offers competitive per-minute rates. Check country availability before selecting — Calling Plans cover fewer countries than Direct Routing.

Operator Connect

Operator Connect offers a balanced solution. Certified carrier partners connect directly to Microsoft via the Teams admin center. You can:

• Choose a carrier from the provided list.
• Provision numbers in the admin center.
• Let the carrier manage the PSTN connection.

No SBC to manage. Available in more countries than Calling Plans. EPC Group recommends Operator Connect when enterprises want carrier flexibility without Direct Routing complexity.

Multinational PSTN architecture

Large multinational organizations rarely use a single connectivity option globally. EPC Group designs hybrid PSTN architectures that match each region to the right connectivity method:

• Direct Routing with local carriers in regions where Calling Plans are unavailable or too expensive.
• Calling Plans in regions where Microsoft offers competitive rates and call patterns are simple.
• Operator Connect where carrier relationships and SLAs are strategically important to the business.

This hybrid approach optimizes cost and carrier relationships across the entire global voice estate.

Multi-site enterprise capabilities

Teams Phone has specific features for multi-site enterprise deployments:

• Location-based routing. Route calls through the local PSTN gateway for regulatory compliance. Required in some countries to prevent toll bypass.
• Dynamic emergency calling (E911/E112). Route emergency calls to the local PSAP based on the user's detected network location. Automatic location detection from corporate network signals.
• Local number assignment. Assign numbers from each country's local carrier for professional local presence in each market.
• Centralized administration. Manage all sites from the Teams admin center with delegated administration permissions per region.
• Survivable Branch Appliance (SBA). Maintain PSTN calling at branch sites that temporarily lose cloud connectivity. SBA provides local call handling without the cloud connection.

Auto-attendants

Auto-attendants manage incoming calls using menu-driven routing. This is a cloud-based alternative to traditional IVR systems. They direct callers to the appropriate destination based on:

• Menu selection
• Time of day
• Dial-by-name input

Auto-attendant design principles

• Keep menu depth to 3 levels maximum — deeper menus frustrate callers
• Provide a path to a live agent at every level
• Configure separate greetings for business hours and after-hours
• Use dial-by-name directories for callers who know their contact
• Nest auto-attendants only when organizational structure requires routing across divisions

Call queues

Call queues route inbound calls to available agents in a defined order. They replace the ACD (automatic call distributor) functionality of legacy PBX systems.

Queue routing methods

• Attendant routing. Ring all agents simultaneously. First to answer gets the call.
• Serial routing. Ring agents one at a time in a fixed order.
• Round robin. Distribute calls evenly across all available agents.
• Longest idle. Route the next call to the agent who has been idle the longest.

Set overflow routing (after a maximum wait time), call timeout routing, and agent opt-in/opt-out to handle demand spikes without caller abandonment.

Compliance recording

Financial services and healthcare organizations must record Teams Phone calls for regulatory compliance. Teams Phone supports compliance recording through certified recording partners.

Certified compliance recording partners

• NICE
• Verint
• ASC Technologies
• Oak Innovation
• Dubber

Compliance recording happens automatically. All calls to or from users with a recording policy are captured. These recordings are kept in the compliance partner's system for the required retention period.

It is important to note that Teams Phone does not store compliance recordings.

Call Quality Dashboard (CQD)

The Microsoft Call Quality Dashboard tracks the quality of Teams Phone calls in your organization. It provides important metrics such as:

• Mean Opinion Scores (MOS)
• Network jitter
• Packet loss
• Round-trip latency for each call

EPC Group uses CQD data at three points in every migration:

1. Pre-migration network readiness assessment — baseline CQD data confirms the network meets Teams voice requirements before migration.
2. Pilot phase validation — CQD confirms call quality meets the target threshold before the full rollout.
3. Post-migration optimization — CQD identifies sites or users with call quality issues for targeted remediation.

Migration phases

EPC Group's standard Teams Phone migration follows five phases:

1. Assessment and design (2–4 weeks). Inventory current PBX, carrier contracts, number ranges, call flows, and fax lines. Design the Teams Phone architecture and connectivity model.
2. Infrastructure setup (2–4 weeks). Configure SBC (for Direct Routing) or provision Operator Connect carrier. Set up Teams Phone licenses, dial plans, and call policies. Build baseline auto-attendants and call queues.
3. Number porting preparation (2–3 weeks). Submit port authorization letters to the losing carrier. Assign temporary Teams numbers for testing. Validate call quality with CQD.
4. Phased user migration (4–8 weeks). Migrate users in waves of 200–500. Each wave includes pre-migration user communication, cutover during low-traffic hours, and a 48-hour intensive support window.
5. Post-migration optimization (2–4 weeks). Tune call quality using CQD. Refine auto-attendant and call queue configurations. Decommission legacy PBX equipment.

Frequently asked questions

What licenses do I need for Microsoft Teams Phone?

To use Teams Phone, you must have a Teams Phone System license. This license comes with Microsoft 365 E5. If you have E3 or other plans, you can add the Teams Phone System add-on.

• The add-on costs $8 per user per month.
• This option will be available starting in 2026.

To use the Phone System, you also need a PSTN connectivity option. Your choices are:

• Calling Plan (Microsoft carrier)
• Direct Routing (your carrier via SBC)
• Operator Connect (certified carrier partner)

Every user who requires a phone number must have both the Phone System license and a PSTN connectivity option.

What is the difference between auto-attendant and call queue in Teams?

An auto-attendant provides menu options to callers and routes them based on their input. This is the "press 1 for sales, press 2 for support" system.

A call queue holds callers in line and connects them to available agents. This is the "your call is important to us, please hold" system.

Auto-attendants can route to call queues. Call queues can overflow to other auto-attendants or voicemail. They work together to handle inbound call volume.

Can Teams Phone replace a contact center (CCaaS)?

Teams Phone with call queues covers basic inbound contact center scenarios: queue routing, agent management, overflow handling, and real-time call dashboards.

Microsoft's solution does not replace full CCaaS platforms like Genesys, Avaya, or Five9. These platforms are essential for complex contact center needs, including:

• Omnichannel support (chat, email, social)
• CRM integration
• Advanced workforce management
• Predictive outbound dialing

Instead, Microsoft partners with contact center vendors to provide deep CCaaS integration with Teams Phone.

How is Teams Phone different from Teams voice calling?

Teams supports VoIP calling between Teams users within the same tenant or across federated tenants at no additional cost — this is Teams-to-Teams calling.

Teams Phone now offers PSTN connectivity. This feature enables users to make and receive calls from any phone number. It supports calls to cell phones, landlines, and external organizations that do not use Teams.

PSTN calling requires two things:

• A Teams Phone System license
• A PSTN connectivity option: Calling Plans, Direct Routing, or Operator Connect

How does Teams Phone handle international calling for multinational organizations?

Multinational Teams Phone deployments typically use a hybrid PSTN architecture. In regions where Microsoft Calling Plans are both available and affordable, organizations utilize these plans. However, in areas where Calling Plans are not available or are expensive, Direct Routing with local carriers is used.

Operator Connect provides an option for regions with certified carrier partners. During the assessment phase, EPC Group develops the hybrid architecture. This process enhances carrier selection by region, with a focus on:

• Cost
• Compliance

Ready to replace your PBX with Microsoft Teams Phone? Contact EPC Group for a Teams Phone assessment and migration plan.