Self-hosted / cloud hosted send/receive fax server
Keep faxing.
Lose the fax machine.
NexusFax converts your analog fax machine into a digital one. Receive faxes as email. Send PDFs as faxes. Enable your whole team with one simple app built for the enterprise. Rest comfortably with SSO and MFA support. No shared machine in a supply closet, no paper jams, no worry.
Why
Fax isn't going away.
Your fax machine can.
Courts still want filings by fax. Insurers still want claims by fax. Clinics, agencies, and suppliers still print a fax number on every form they hand you. None of that is changing anytime soon — fax is one of the few document formats every regulator and legacy system already trusts.
What can change is the machine. A physical fax ties your whole team to one box in a closet, with no login and a habit of jamming at the worst possible moment. NexusFax keeps your trusted number and turns everything else digital.
How it works
Two directions, both boring in the best way
Upload a document, pick a number, hit send. NexusFax hands it straight to the SIP Provider and emails the sender the final result in plain-English.
As a fax comes in, NexusFax verifies it's genuine with digital signatures. NexusFax matches the number to the mapped email address and sends it as an email attachment. Unmapped numbers fall back to a catch-all address.
See it in action
What your team actually looks at
Sending a fax — pick a number, attach a PDF, done.
Sign-in — local or SSO, MFA on every local login.
Admin panel — every user, number, and MFA status in one table.
Features
Built for a team, without the team tax
One number, one person
Every user gets their own fax number to send from and receive on. Need a shared line instead? Assign send-only users to someone else's number.
Sign in the way you already do
Local accounts and SAML single sign-on work side by side. Turn on SSO without losing a break-glass admin login that still works if it's ever misconfigured.
Secure every login with MFA
MFA codes from an authenticator app are required on every local sign-in.
Faxes become email
Inbound faxes land as an email attachment in the right inbox automatically. Outbound faxes get a confirmation email too, success or failure.
Runs on your infrastructure
Ships as a Docker container. On the self-hosted plan, your documents and data stay on the hardware you choose and control.
An admin panel that makes sense
Add a person, add a number, connect the two. Reset a forgotten password or a lost authenticator app in a couple of clicks.
Security
Faxed documents are often sensitive. Treat them that way.
Contracts, medical referrals, signed agreements, insurance claims — the kind of paperwork that still travels by fax is exactly the kind you don't want sitting around unprotected.
- ✓Passwords are hashed with bcrypt and never written to a log.
- ✓Every inbound fax is cryptographically verified before it's trusted as genuine.
- ✓Session cookies are locked down — httpOnly, secure, same-site.
- ✓Every action that changes data is protected against cross-site forgery.
- ✓The app runs as a non-root user on a read-only container filesystem.
- ✓Documents are handled in memory only — nothing lingers on disk after delivery.
Pricing
Two ways to run it
1 price, unlimited users and use. No hidden fees or SSO tax.
Buy the license once and run it on your own server forever. Professional installation is included, so it's set up right from day one.
- Full application, no recurring license fee
- Runs entirely on your infrastructure
- Professional installation included. We'll configure the SIP Provider, SSO, and MFA for you*
- Your documents never touch a third-party server
We host it, patch it, and back it up. Your team just uses it.
- Fully hosted and maintained by us
- Predictable monthly cost
- No server, no Docker, no upkeep on your end
- Cancel anytime
*Exact details on professional installation vary based on your existing IT infrastructure. Contact us for details.
Questions
Common questions
Do we need a SIP Provider?
Yes. NexusFax sends and receives using a fax API, so you'll need a SIP Provider and at least one fax-enabled number. You can move just your fax number to SIP if you wish.
Does it work with our existing single sign-on?
If your identity provider supports SAML, yes. Local accounts stay available too in case you don't wish to integrate and as a fallback login that keeps working in the event your SSO breaks.
Can more than one person share a fax number?
Yes. You can add "send-only" users who send from someone else's number without owning a number themselves — useful for a shared department line.
What happens to documents after they're sent or received?
Documents are handled in memory during transmission, not stored on disk ever. Received faxes are sent straight from memory to the email to the mapped recipient.