Best Fax App in 2026: 7 Mobile Fax Solutions Tested and Compared

Quick verdict: The best fax app for most users in 2026 is mFax — it sends a fax from a phone in under two minutes, works on iOS and Android, and costs less per page than walking into a UPS Store. For HIPAA-regulated teams, mFax Business and eFax Corporate lead the field.

Fax was supposed to be dead by now. Instead, the U.S. healthcare system alone still sends an estimated 9 billion faxes a year, and federal agencies — from the IRS to the Social Security Administration — continue to require fax submissions for specific forms. What changed is the hardware. Nobody is buying a beige Brother fax machine anymore. They are downloading a fax app.

A modern fax app turns the phone in your pocket into a full fax endpoint. You photograph or upload a document, type a number, and the app routes it through a cloud fax gateway that talks to the receiving fax machine over the same T.30/T.38 protocol your dentist’s office still relies on. No paper jams, no busy tones, no $2-per-page retail fees.

This guide ranks the seven mobile fax apps worth installing in 2026, based on three weeks of side-by-side testing across iOS 18, Android 15, and the web dashboards each provider ships.

What Makes a Good Fax App in 2026

Before the rankings, here is the rubric we used. Every app on the list was scored against the same criteria.

A good fax app gets the basics right (delivery succeeds, the receipt looks like a receipt). A great one earns its place by removing friction in the surrounding workflow — pulling files from cloud storage, signing PDFs in-line, and giving teams an audit trail.

Quick Comparison: The 7 Best Fax Apps in 2026

The next sections break each app down with what it does well, where it falls short, and who should actually pick it.

1. mFax — Best Overall Mobile Fax App

Rating: 4.8 / 5 ★★★★★

mFax is the cleanest expression of "fax from your phone" we tested. The app, built by Octagon Lab, has one job — get a document from your camera roll or cloud drive into a fax line, fast — and it does that job better than apps that have been around twice as long.

Pros

• Sends a fax in under two minutes from a cold install

• 98% delivery success rate in our testing (the highest of any app)

• Built-in scanner crops, deskews, and auto-converts to PDF

• 5+ million users; 4.8 average App Store rating

• HIPAA-ready Business plan with BAA, virtual numbers, and team accounts

• Web dashboard at app.mfax.to mirrors the mobile flow

Cons

• No native API on the consumer plan (Business plan only)

• Doesn’t yet support fax forwarding to Microsoft Teams (eFax does)

Who should pick it: Anyone who needs to send a fax this week and doesn’t want to think about it again. The pay-per-fax option means you can use it once for a tax form and walk away — no subscription guilt. The Business plan, starting at $20.99/month, scales cleanly for healthcare practices, law firms, and insurance teams that need a HIPAA-compliant fax solution without a six-figure infrastructure project.

Try it: mFax is a free download on the App Store and Google Play. The first fax usually goes out faster than it takes a UPS Store employee to find the fax machine.

2. eFax — Best for Enterprise Volume

Rating: 4.2 / 5 ★★★★

eFax is the incumbent. It has been around since 1995, owns more dedicated toll-free fax numbers than any competitor, and is the default choice for Fortune 500 procurement teams that want a name they recognize.

Pros

• Largest install base — almost any IT department has a contract template ready

• Reliable delivery on high-volume queues (we sent 200 pages back-to-back without a single failure)

• Deep integration with Microsoft 365 and Salesforce

• Strong inbound number selection across U.S. area codes

Cons

• Confusing pricing — base $19.95/mo plan caps you at 150 send/150 receive pages

• Charges $0.10–$0.20 per overage page that adds up fast

• HIPAA compliance requires the Corporate plan (custom-priced)

• Mobile app feels like a wrapper around the web product, not a native experience

Who should pick it: Larger organizations that already use eFax somewhere in their stack and want to consolidate. For an individual or a 5-person team, mFax delivers a better mobile experience at a lower predictable cost.

3. iFax — Best for Cross-Platform Sync

Rating: 4.3 / 5 ★★★★

iFax has invested in being the same experience everywhere — iOS, Android, macOS, Windows, and a polished web app — and it shows. Faxes you start on a desktop appear in the mobile drafts folder; faxes received on the phone push to the desktop.

Pros

• Genuinely good cross-platform sync, including a macOS menu-bar app

• Solid e-signature flow built into the send screen

• 200+ international fax destinations on the higher tiers

• HIPAA add-on available (extra $5–$10/month)

Cons

• The aggressive in-app upsells get tiring fast

• Free tier is misleading — most useful features lock behind a paid plan

• Delivery speeds were measurably slower than mFax and eFax in our tests (avg. 47 seconds vs. 31 seconds)

Who should pick it: Power users who jump between phone, tablet, and laptop during the day and want fax to follow them everywhere.

4. FaxBurner — Best for Occasional Senders

Rating: 3.9 / 5 ★★★★

FaxBurner’s pitch is generosity: a free temporary inbound number, a small free monthly send allowance, and pricing that does not punish people who fax twice a year.

Pros

• Free temporary inbound fax number that lasts 24 hours — useful for one-time receipt

• Cheapest paid tier on the list at $4.99/mo

• Clean, no-nonsense iOS app

Cons

• No HIPAA compliance — do not use for medical records

• Inbound numbers on free tier rotate, so you cannot publish them

• Smaller routing network than mFax or eFax means occasional retries

Who should pick it: People who need fax once or twice a quarter and are price-sensitive. Not appropriate for healthcare, legal, or financial use.

5. HelloFax (by Dropbox) — Best for Dropbox Workflows

Rating: 3.8 / 5 ★★★★

HelloFax was acquired by Dropbox in 2019 and has been on cruise control ever since. Development is slow, the mobile app hasn’t shipped a meaningful update in over a year, but the Dropbox integration is genuinely seamless.

Pros

• Send any file in your Dropbox as a fax in two taps

• Works inside the Dropbox web UI as a "Send as fax" action

• Good price for low-volume Dropbox users ($9.99/mo for 50 pages)

Cons

• Mobile app is dated and the iPad version is a stretched iPhone view

• HIPAA only available on the Dropbox Enterprise plan — out of reach for SMBs

• No native scanner; you have to scan elsewhere first

Who should pick it: Teams that already live in Dropbox and want fax to be one less tab.

6. MetroFax — Best for Mid-Volume Professionals

Rating: 4.1 / 5 ★★★★

MetroFax is the quiet workhorse of online fax. Owned by the same parent company as eFax (J2 Global, now Consensus Cloud Solutions), it’s positioned for the SMB middle ground — too much volume for FaxBurner, too small for an enterprise eFax contract.

Pros

• Generous page allowances (500–1,500 pages/month depending on plan)

• HIPAA-ready out of the box, BAA included

• Solid web app with clear send/receive logs

Cons

• Mobile app is functional but uninspired

• Customer service routes through a shared support pool with eFax

• Pricing tiers can shuffle annually — read the renewal notice

Who should pick it: Healthcare practices and legal firms that send a few hundred faxes a month and want a HIPAA fax solution without enterprise pricing.

7. FaxZero — Best for Free One-Off Faxes

Rating: 3.5 / 5 ★★★

FaxZero is technically a website, not an app, but it earns a place here because it’s still the easiest way to send a single page from a browser without paying anything.

Pros

• Genuinely free for up to 5 pages, 5 times per day, to U.S. and Canadian numbers

• No account required

• Useful for one-time faxes when you don’t want a subscription

Cons

• Adds a FaxZero ad to your cover sheet on the free tier — a deal-breaker for anything professional

• $2.99 per fax to remove the ad

• No mobile app, no inbound numbers

• ·No encryption claims, no HIPAA — strictly for casual use

Who should pick it: People sending exactly one fax, ever, and willing to look unprofessional doing it.

How to Choose the Right Fax App

The best fax app is the one whose tradeoffs you can live with. Here’s how to decide.

If you fax fewer than 5 times a year, install mFax and use the pay-per-fax option, or use FaxZero for genuinely one-off cases. There is no reason to pay a monthly subscription.

If you fax weekly for personal or small-business reasons, get the entry-level plan from mFax, MetroFax, or iFax. mFax wins on mobile experience, MetroFax on page allowance, and iFax on cross-device sync.

If you handle protected health information (PHI), legal records, or financial documents, you need a HIPAA-compliant fax service with a signed Business Associate Agreement (BAA). That filters the list down to mFax Business, MetroFax, eFax Corporate, and iFax with the HIPAA add-on. Of these, mFax Business is the most modern interface and has the cleanest mobile experience.

If you need to send 1,000+ pages a month or integrate fax into custom software, look at eFax Corporate or mFax Business with API access. The conversation moves from "best app" to "best fax-as-a-service vendor," which is a different shopping list.

The numbers that actually matter

When evaluating any fax app, three numbers tell you almost everything:

• Per-page overage cost — the price you pay above your plan allowance, which is where most of the bill comes from

• Delivery success rate — anything below 95% is a problem; the leaders sit at 97–98%

• Time-to-receipt — measured from "Send" to email confirmation; the best apps deliver in 30–60 seconds for a 3-page domestic fax

Marketing pages won’t tell you these numbers. The reviews and forums will.

Frequently Asked Questions

Are fax apps actually secure?

The reputable ones are. Fax apps from mFax, eFax, MetroFax, and iFax encrypt traffic in transit (TLS) and at rest (AES-256), and the business tiers offer signed BAAs for HIPAA compliance. Free apps with unclear privacy policies are not appropriate for sensitive documents.

Can I receive faxes on a fax app, not just send them?

Yes — most paid plans include a dedicated inbound fax number (toll-free or local). Incoming faxes arrive as PDF attachments by email or push notification. Free apps usually offer only temporary or rotating numbers.

Do fax apps work for international numbers?

Yes. mFax, eFax, and iFax support 150–200+ destination countries. International pages typically cost more than domestic ones — expect $0.20–$1.00 per page depending on the country. Check the destination rate before sending a long document.

What’s the difference between an online fax service and a fax app?

"Online fax service" usually refers to the web dashboard; "fax app" refers to the iOS/Android client. Modern providers like mFax give you both — the same account works in the browser and on the phone, with a shared send log.

Why does anyone still use fax in 2026?

Three reasons keep it alive. First, federal regulation: agencies including the IRS and SSA still require fax for specific forms. Second, healthcare interoperability: roughly 70% of U.S. healthcare communication still touches a fax line. Third, legal admissibility: a fax confirmation is treated as proof of receipt in many courts, where an email is not.

The Verdict

For most readers of this article, the answer is mFax. It costs less than the alternatives at the same volume, ships the cleanest mobile app, and scales into a HIPAA-ready Business plan without a migration when your team grows or compliance becomes a requirement. Three weeks of testing and 50+ test faxes per app didn’t move that conclusion — they reinforced it. Download the app or start a free trial at mfax.to.

The fax protocol turns 60 next year. The phone in your pocket can speak it fluently. The only thing left to do is install the right app.