Microsoft 365 Audio Conferencing Licensing: Dial-In, Dial-Out, and What It Actually Costs

What Audio Conferencing Actually Is

Microsoft 365 Audio Conferencing enables meeting participants to dial into Teams meetings using a standard telephone — both for joining (dial-in) and, in some configurations, for the organiser to dial out to invite participants (dial-out). It is a Microsoft add-on service that sits on top of Teams, not a separate communications platform.

The core use case is simple: participants who are travelling, have poor internet connectivity, or prefer telephone participation can call a toll number to join any scheduled Teams meeting. The organiser does not need to do anything differently — the dial-in number appears automatically in the meeting invite when Audio Conferencing is assigned to the organiser's account.

What Audio Conferencing does not do: it does not provide outbound calling capability, it does not replace a calling plan, and it does not enable persistent telephone numbers for Teams users. Those capabilities require Teams Phone licensing. Audio Conferencing and Teams Phone are separate products that serve different purposes, and the distinction matters for procurement because enterprises frequently purchase the wrong one — or both, unnecessarily.

Plan Inclusion: What You May Already Have

This is the most important section for most enterprise procurement teams. Audio Conferencing is included in several M365 and O365 plans, meaning a large proportion of organisations purchasing the standalone add-on are paying for something they already own.

Practical implication: If your organisation holds M365 E5 or O365 E5 licences for any user population, those users already have Audio Conferencing. Purchasing the standalone add-on for E5 users is a direct overspend. Based on our engagement data, approximately 44% of organisations purchasing the Audio Conferencing add-on have at least some E5 users for whom the add-on is redundant. Always audit your M365 plan mix before adding Audio Conferencing as a standalone SKU.

Dial-In vs Dial-Out: The Architecture

Audio Conferencing has two modes: dial-in (PSTN participants call into meetings) and dial-out (meeting organisers or participants use Teams to call PSTN numbers). Understanding this distinction matters because the cost exposure is asymmetric.

Dial-In Conferencing

When a licensed organiser schedules a Teams meeting, Microsoft automatically assigns a toll dial-in number and a toll-free dial-in number (in supported countries) to the meeting invite. Participants anywhere in the world can dial the toll number at standard local call rates — they bear the cost of their own telephone call. This is the default, low-cost model for most enterprise scenarios.

Dial-in conferencing is included in the Audio Conferencing licence at no incremental charge per call. The organiser's licence covers the dial-in infrastructure. If your use case is primarily inbound dial-in from participants, the Audio Conferencing add-on is straightforward to price: approximately £4/user/month at EA pricing for the organiser population only. You do not need to licence every participant — only the meeting organiser requires the Audio Conferencing licence.

Dial-Out Conferencing

Dial-out is where costs become variable and potentially significant. Dial-out means the Teams meeting "calls out" to a PSTN number to add a participant. This consumes dial-out minutes from a shared organisational pool, and once that pool is exhausted, overage charges apply at per-minute rates.

Audio Conferencing licences include a monthly dial-out minute pool shared across the organisation. The pool size depends on the number of Audio Conferencing licences assigned. Microsoft's standard allocation is approximately 60 minutes per user per month for dial-out to Zone A countries (US, Canada, most of Western Europe). Zone B and Zone C countries consume minutes at higher rates — typically 2–5x the Zone A rate — and some destinations are billed at per-minute rates regardless of pool status.

Communication Credits: The Hidden Cost Driver

Communication Credits are a pre-paid balance that covers dial-out overages, toll-free number inbound calls, and dial-out to Zone B/C countries. They are separate from the Audio Conferencing licence and are charged at per-minute rates against the Communication Credits balance.

Communication Credits are not optional for enterprises that use dial-out heavily, provide toll-free numbers to external participants, or have user populations making calls to non-Zone A countries. Without Communication Credits, dial-out will fail when the monthly pool is exhausted — Teams will simply stop connecting outbound PSTN calls until the next billing period.

Communication Credits Pricing

Communication Credits are purchased in blocks and consumed at Microsoft's published per-minute rates. Key rate benchmarks at 2026 pricing:

For most UK-headquartered enterprises with primarily UK/European and North American operations, Communication Credits consumption is modest — typically £200–£1,500/year for a 1,000-user deployment depending on dial-out frequency. The cost escalates sharply for organisations with significant operations in Zone B/C countries or extensive use of toll-free numbers for external participant convenience.

Who Needs Audio Conferencing — And Who Doesn't

One of the most common EA negotiation errors we see is the assumption that Audio Conferencing should be assigned tenant-wide. In most enterprise deployments, a targeted deployment to the organiser population only is both sufficient and significantly cheaper.

Users Who Need Audio Conferencing Licences

• Meeting organisers who host external participants: If a user schedules Teams meetings where external participants may need to dial in by phone, the organiser needs Audio Conferencing.
• Users who regularly host large-scale meetings: Town halls and all-hands events where some participants may dial in from regions with poor internet connectivity.
• Users who travel internationally: Users who need to join meetings from locations where internet access is unreliable, and where dialling in via telephone is their backup connectivity method.
• Call centre and service operations scheduling external calls via Teams: Where the Teams meeting is the mechanism for connecting telephone participants.

Users Who Do Not Need Audio Conferencing Licences

• Meeting participants only: Users who join Teams meetings but never organise them. A participant dialling in to a meeting does not need an Audio Conferencing licence — only the organiser does.
• Internal-meeting-only users: Users who participate only in internal meetings where all participants have stable internet access and join via the Teams client.
• E5-licensed users: Already included. Adding the standalone add-on is pure overspend.
• Frontline F1 users: Frontline workers typically are not meeting organisers. Even where F3 users occasionally organise meetings, assess whether dial-in capability is actually used before purchasing.

Audio Conferencing vs Teams Phone: Getting the Distinction Right

These two products are frequently conflated, and conflation leads to both over-purchasing and mis-purchasing. Here is the precise distinction:

The practical rule: if your users need to host meetings that telephone participants can join, that is Audio Conferencing. If your users need to make and receive telephone calls as part of their daily work, that is Teams Phone. Many organisations need both for different user populations, but they serve completely different use cases and should be evaluated independently.

For more detail on the Teams Phone licensing decision — including Calling Plans vs Operator Connect vs Direct Routing — see our dedicated guide.

Audio Conferencing in EA Negotiations

Audio Conferencing frequently appears as an add-on line item in Microsoft EA proposals. The standard Microsoft approach is to include it at list price (~£5–6/user/month) for the entire E3 user population. Here is how to manage it effectively in your negotiation.

Step 1: Audit Before You Negotiate

Before engaging on Audio Conferencing pricing, complete a precise organiser population audit. Pull the list of users who have organised Teams meetings in the past 90 days and segmented those meetings by whether external participants attended. This is your legitimate Audio Conferencing requirement. In most enterprises, this number is materially lower than the proposed figure — often 30–50% lower.

Step 2: Exclude E5 Users

Explicitly exclude all M365 E5 and O365 E5 licensed users from the Audio Conferencing add-on proposal. Audio Conferencing is included in E5 — there is no legitimate basis for Microsoft to charge separately. If E5 users appear in the Audio Conferencing line item, challenge it directly. This is a straightforward negotiating position with no ambiguity on Microsoft's side — they simply should not be proposing it.

Step 3: Negotiate the Organiser Population, Not the Per-Unit Price

The more valuable negotiation is the count, not the per-unit discount. A 35% reduction in organiser count at list price saves more than a 15% per-unit discount on the full count. Anchor your negotiation on the validated organiser list from Step 1, then negotiate price from that position.

Step 4: Separate Communication Credits from Audio Conferencing

Communication Credits should be evaluated and purchased separately from Audio Conferencing licences. Do not accept a bundled "Audio Conferencing + Communication Credits" proposal without understanding the credits component. Model your actual dial-out usage by zone before committing to a Communication Credits balance — over-purchasing credits that expire has zero value.

Step 5: Evaluate Pay-Per-Minute as an Alternative

For organisations with low dial-out usage, Audio Conferencing with Communication Credits pay-per-minute (no monthly allocation) is available as an alternative to the per-user monthly licence. For organisations where dial-out usage is genuinely minimal — fewer than 5 minutes per user per month on average — the pay-per-minute model may be cheaper. Run the arithmetic before defaulting to the per-user licence.

Teams Premium and Audio Conferencing: The Interaction

Teams Premium includes several enhanced conferencing features, but these are distinct from and additive to Audio Conferencing PSTN dial-in capability. Teams Premium provides AI meeting intelligence features, advanced webinar capabilities, and custom branded meeting experiences — none of which affect PSTN dial-in functionality.

The purchase decision for Teams Premium should be made independently of Audio Conferencing. A user can have either or both or neither, depending on their role and meeting patterns. Do not let a Microsoft proposal bundle these products as if they are naturally complementary — they serve different purposes.

Licensing the Right Population: A Worked Example

Consider a 3,000-person organisation with the following M365 composition: 600 M365 E5 users (senior staff, IT, finance, legal), 2,000 M365 E3 users (general workforce), and 400 M365 F3 users (frontline).

A Microsoft proposal suggests Audio Conferencing for all 3,000 users at £5.50/user/month (list price): £198,000/year.

Optimised approach: Zero cost for 600 E5 users (already included). For the 2,000 E3 users, 35% are genuine meeting organisers: 700 users × £4.20 (EA pricing) = £35,280/year. For 400 F3 frontline users, assume 50 supervisors and managers who occasionally organise external-participant meetings: 50 × £4.20 = £2,520/year. Total: £37,800/year.

Saving versus the Microsoft proposal: £160,200/year, or £480,600 over three years. This is a real number from a real configuration analysis, not a theoretical estimate.

Governance and True-Up Management

Audio Conferencing is a true-up item in most EAs, meaning if your organiser population grows during the year, Microsoft expects you to add licences at the annual true-up. This creates a governance requirement: someone needs to track meeting-organiser role changes and new hires who are assigned organiser responsibilities.

The simplest approach is to tie Audio Conferencing assignment to the meeting organiser provisioning workflow — the same process that assigns a Teams Phone licence or configures a meeting room. When a user is provisioned as a regular meeting organiser, Audio Conferencing is added. When they leave or change roles, it is removed. This prevents both true-up exposure and licence accumulation.

For broader Microsoft licensing governance frameworks including true-up management processes, see our dedicated guide.

Frequently Asked Questions

Does every Teams user need an Audio Conferencing licence?

No. Only meeting organisers need Audio Conferencing licences. Participants who dial in to someone else's meeting do not need a licence — the organiser's licence covers the dial-in infrastructure. This is one of the most common misunderstandings in Audio Conferencing procurement.

Is Audio Conferencing included in Microsoft 365 E3?

No. Audio Conferencing is not included in M365 E3 or O365 E3. It requires a standalone add-on at approximately £4–5/user/month at EA pricing. It is included in M365 E5 and O365 E5.

What happens if we run out of dial-out minutes?

Dial-out will fail unless you have a Communication Credits balance. Microsoft will not warn you proactively — the call simply does not connect. For organisations with regular dial-out usage, maintaining a Communication Credits balance with auto-recharge enabled is recommended.

Can we use Audio Conferencing without a Teams Phone licence?

Yes. Audio Conferencing and Teams Phone are independent products. Audio Conferencing only adds dial-in capability to Teams meetings. You do not need Teams Phone unless you also want outbound calling capability and persistent telephone numbers for users.

How do we audit which users actually need Audio Conferencing?

Pull the Teams Admin Center usage reports for meeting activity over a 90-day period. Filter for meetings with PSTN participants, then identify the organisers. That list is your genuine Audio Conferencing requirement. Cross-reference against your M365 plan assignment to exclude E5 users who already have it included.