Microsoft Teams Fax: How to Send Faxes via Teams

By David Thompson · Published December 22, 2024 · Updated June 8, 2026 · 7 min read

Quick Answer: Microsoft Teams has no built-in fax feature. The fastest way to fax from Teams is to use an email-to-fax service: compose an email to [faxnumber]@send.mfax.to, attach your PDF, and send. Try it free at mFax.to.

Microsoft Teams is the default communication hub for over 320 million monthly active users, but it cannot send or receive faxes on its own. If your organization runs on Teams and still needs to fax documents — for healthcare, legal, government, or financial workflows — you need a third-party solution.

This guide covers three ways to send faxes from Microsoft Teams, from the simplest to the most integrated. You don't need a fax machine, a phone line, or IT support for any of them.

Why Teams Doesn't Include Fax

Microsoft Teams is built for chat, video calls, and file collaboration. Fax uses a completely different protocol (T.38/T.30 over phone lines), and Microsoft has never added native fax support to Teams or Microsoft 365.

This means every Teams user who needs fax has three options:

1. Email-to-fax via Outlook (the simplest — works today, no install)
2. Third-party Teams apps from the marketplace (integrated into Teams UI)
3. Web-based fax services like mFax (browser upload, works alongside Teams)

Method 1: Email-to-Fax via Outlook (Recommended)

Since Outlook and Teams are part of the same Microsoft 365 ecosystem, this is the most practical approach. You send a fax as an email — and Teams notifications, chat, and Outlook mail all live in the same workspace.

Method 2: Third-Party Teams Marketplace Apps

The Microsoft Teams App Store includes several fax-specific apps. These embed a fax interface directly inside Teams, so you never leave the Teams window.

Available Teams Fax Apps

How Teams Fax Apps Typically Work

1. Install the app from the Teams App Store (admin approval may be required)
2. Connect your fax account with the third-party provider
3. Open the fax app inside Teams (appears in the sidebar or as a chat bot)
4. Enter the fax number and attach your document
5. Send — the app handles conversion and delivery

Pros and Cons of Teams Marketplace Apps

Method 3: Web-Based Fax (Works Alongside Teams)

If you don't want to install anything or wait for IT approval, use a browser-based fax service in a tab next to Teams.

1. Open mFax.to in your browser (or pin it as a Teams tab)
2. Upload your PDF — or use the document converter for other file types
3. Enter the recipient's fax number
4. Click Send

This method works on any device, any browser, and doesn't require admin permissions. You can even pin the mFax website as a Teams tab for quick access:

1. In any Teams channel, click the + button to add a tab
2. Choose Website
3. Enter https://mfax.to as the URL
4. Name the tab "Fax" and save

Now your team has a fax button right inside their Teams channel — no marketplace app needed.

Which Method Should You Choose?

For most Teams users, email-to-fax is the fastest path. You're already in Microsoft 365 — just send a fax as an email from Outlook, and it shows up alongside your Teams conversations.

For large organizations that want fax baked into the Teams interface with SharePoint integration and centralized billing, a marketplace app may be worth the setup effort.

Sending Faxes to Common Destinations

Teams users in healthcare, legal, and finance often fax to the same destinations. Here are quick links to our guides:

• IRS forms — see our IRS fax numbers directory and how to fax to the IRS
• Medical records — follow our HIPAA fax guide and how to fax medical records securely
• Legal documents — use a professional fax cover sheet for court filings and contracts

Need a cover sheet? Generate one free with our fax cover sheet generator.

Security and HIPAA Compliance

If your organization handles Protected Health Information (PHI), financial data, or legal documents, your fax solution must meet compliance requirements.

What to verify before faxing from Teams:

• Encryption — TLS in transit, AES-256 at rest
• BAA — the fax provider must sign a Business Associate Agreement
• Audit trail — delivery confirmations with timestamps
• Access control — no shared logins; enforce MFA
• Data retention — understand where faxed documents are stored and for how long

Outlook-to-fax is encrypted in transit by default (TLS 1.2+). The fax provider handles encryption on the outbound leg. For full HIPAA compliance, use mFax Business — it includes encryption, BAA, and audit logging out of the box, starting at about $9/mo.

For a deeper dive, read our guide to HIPAA compliant faxing and our breakdown of whether online fax is secure.

Troubleshooting

Teams fax app won't install?

• Your Teams admin may need to approve third-party apps. Ask IT to allowlist the fax app in the Teams Admin Center under Manage Apps.
• In the meantime, use email-to-fax (Method 1) — it requires zero admin permissions.

Fax not delivered?

• Verify the fax number includes the country code (1 for US/Canada) with no dashes or spaces.
• Check that the recipient's fax machine is on and not busy.
• Try resending — the service retries automatically, but a manual resend can help if the line was temporarily down.

Attachment not converting?

• Switch to PDF for the cleanest result. Save Word or Excel files as PDF first.
• Remove password protection — fax gateways cannot open encrypted files.
• Keep file size under 20 MB per fax.

No delivery confirmation?

• Check your Outlook Spam/Junk folder.
• Verify your fax service account is active and your email is registered.

For more diagnostics, see our guide to sending a test fax.

Start Faxing from Teams Today

Microsoft Teams doesn't include fax — but you don't need it to. The fastest way for any Teams user to send a fax is:

1. Sign up at mFax.to
2. Open Outlook, compose a new email
3. In the To field, type [faxnumber]@send.mfax.to
4. Attach your PDF and click Send

No fax machine. No phone line. No IT tickets. Just send.

For business teams, mFax Business gives you a dedicated virtual fax number, team accounts, HIPAA compliance, and a web dashboard — starting at about $9/mo. There are no rigid fixed tiers: build your own plan with a live calculator, choosing the exact number of seats and pages your team needs and paying only for what you use.