LAN Fax: How to Send and Receive Faxes Over a Network

What is LAN fax?

LAN fax (Local Area Network fax) is a feature on many multifunction printers that lets you send and receive faxes over your office network instead of connecting the printer directly to a telephone line. The printer uses its network interface (Ethernet or Wi-Fi) to communicate with a fax server, a computer running fax software, or another fax-capable device. The actual fax transmission still travels over the public switched telephone network (PSTN) or a voice over IP (VoIP) service, but the printer itself does not need a phone jack.

With LAN fax, you typically scan the document at the printer, select a fax destination from an address book or enter a number, and the printer sends the image over the network to a fax server. The server then dials the destination and transmits the fax. For receiving, inbound faxes come to the fax server, which routes them to the printer for printing or to an email inbox. Some printers also support direct IP faxing, where two network-capable fax devices communicate without a server, using protocols like T.38 or SIP, though that is less common in consumer equipment.

LAN fax vs. phone line fax

A traditional phone line fax setup requires a dedicated analog phone line for each fax machine. You plug the printer into a wall jack, and it uses the phone line to dial and transmit. This works reliably but ties up a line and often incurs an extra monthly charge. LAN fax removes the need for a physical phone line at the printer. Instead, the printer uses your existing network, and the fax server handles the phone line connection centrally. This means one phone line can serve many users and multiple printers.

The tradeoff is added complexity. LAN fax requires a properly configured network, a fax server or compatible software, and often IT involvement. Phone line fax is simpler and more reliable for small offices with a single fax machine. For a home office, a phone line fax might be sufficient. For a busy office with multiple workstations, LAN fax reduces cabling and allows users to send faxes from their computers without walking to the printer.

Benefits of LAN fax

The main benefit of LAN fax is cost savings. You avoid paying for a dedicated phone line at each printer. If you already have a fax server or a VoIP subscription that includes faxing, LAN fax lets you centralize fax traffic and spread the cost over the entire office. Another advantage is convenience: users can send faxes directly from their desktop applications using the printer's scanning and network capabilities, and incoming faxes can be routed to email as PDF attachments, reducing paper waste.

LAN fax also simplifies management. Instead of maintaining multiple phone lines and fax machines, you have one server that all printers connect to. This makes it easier to track fax usage, apply security policies, and update fax settings across the fleet. Many multifunction printers with LAN fax also support scan to email and network scanning, so you can digitize documents and send them to recipients without any physical phone line.

Limitations and when to stick with a phone line

LAN fax is not always the best choice. It depends on your office's network reliability and IT support. If your network goes down, faxing stops. A dedicated phone line fax machine works even during a network outage. Also, setting up LAN fax correctly requires technical knowledge. You need to configure the printer's network settings, install fax server software (or use an online fax service), and ensure the server's firewall allows fax traffic. For a small office with no IT staff, this can be a hurdle.

Another limitation is that LAN fax often requires a fax server or an internet fax service to complete the call. If you use an online fax service, you must have a broadband internet connection and a subscription. If you rely on a local fax server with a modem, you still need a phone line at the server. So LAN fax shifts the phone line requirement to the server, not eliminates it. For occasional faxing, a simple one-line fax machine may be more practical. Look for a multifunction printer with fax capabilities that supports both traditional phone line and LAN fax, giving you flexibility.

Setting up LAN fax on a multifunction printer

Most business-oriented multifunction printers from major brands like Brother, Canon, HP, and Xerox include LAN fax in their specification sheets. The exact setup steps vary, but the general process is consistent. First, connect the printer to your network using Ethernet or Wi-Fi and assign it a static IP address from the printer's control panel or web interface. Then, enable the fax feature and choose the LAN fax mode. You will usually specify the fax server address or the IP of the recipient for direct IP faxing.

On the server side, install fax server software that supports the printer's protocol. Many fax servers use standard protocols like SMTP for email-to-fax or T.38 for VoIP. The Printer Working Group (PWG) has defined standards like IPP Everywhere that allow network printers to be discovered and used without vendor-specific drivers, which simplifies setup for printing and scanning, though fax is less standardized. For sending faxes from a computer, you might use the printer's driver with a fax option or a dedicated application. The printer's manual will provide model-specific instructions.

What to look for in a LAN fax capable printer

When shopping for a printer with LAN fax, check that it has an Ethernet port or dual-band Wi-Fi for stable network connectivity. Look for support for common network fax protocols, such as IPP Fax or SMTP, and compatibility with your fax server or online fax service. Energy efficiency is also worth considering; ENERGY STAR certified imaging equipment must meet strict power management criteria, including automatic duplexing and sleep modes, which helps reduce running costs. You can find certified models on the ENERGY STAR product finder by visiting their website.

Consider the printer's scanning capabilities. A document feeder (ADF) is essential for multi-page faxes, and duplex scanning is a plus. Also, check if the printer can send faxes to email (scan to email) so you can receive faxes digitally. Many all-in-one printers offer these features as part of a home office or small business configuration. Finally, verify that the printer's firmware supports your network environment; some printers require updates to work with newer authentication methods like WPA3.

What to pick for your use

Questions

Do I need a phone line for LAN fax?

Not at the printer itself. The printer connects to the network, and the actual fax transmission happens through a fax server or an online fax service. That server still needs a phone line or a VoIP subscription, but you avoid a dedicated line at each printer.

Can I send a fax from my computer using LAN fax?

Yes, many LAN fax setups allow you to send faxes from your computer by using the printer's driver or a fax client. The document is sent over the network to the printer's fax function, which then transmits it via the fax server.

Does LAN fax work with VoIP?

It can, but compatibility depends on the fax server and VoIP provider. Traditional fax over analog lines is more reliable. If using VoIP, look for a provider that supports T.38 fax relay to avoid transmission errors.

Can I receive faxes without a phone line using LAN fax?

Yes, incoming faxes arrive at your fax server or online fax service, which can deliver them to the printer for printing or directly to your email as a PDF. This is a common way to go paperless.

Is LAN fax more expensive than a regular phone line fax?

Initially, LAN fax can require a printer with advanced networking and a fax server license, which may cost more. Over time, you save on phone line charges and paper, especially in an office with many users.