What Happens to Fax Machines After the PSTN Switch-Off?

Fax machines have been a staple of business communication for decades. Legal firms, medical practices, logistics companies, and financial services still rely on them daily. But with the PSTN switch-off in January 2027, the copper phone lines that fax machines depend on will stop working. So what happens to your fax machine — and how do you keep faxing?

This guide explains your options, from fax-to-email services to analogue adapters, so you can make the right choice for your business.

Why the PSTN Switch-Off Affects Fax

Traditional fax machines work by sending and receiving data over analogue phone lines. They use audible tones (the familiar screeching sound) to transmit page images over the PSTN. When the copper network is decommissioned, fax machines connected to analogue lines will simply stop working.

This applies to:

• Standalone fax machines connected to a phone socket
• Multifunction printers with built-in fax connected to an analogue line
• Fax modems in servers or PCs connected to a phone line

If your fax machine connects to an analogue phone line, it will be affected.

Can Fax Work Over VoIP?

In theory, fax can work over VoIP, but it is unreliable. Fax communication was designed for circuit-switched analogue networks where the connection is continuous and predictable. VoIP, by contrast, uses packet-switched networks where data is broken into packets and reassembled at the other end.

The problems include:

• Packet loss: Even a tiny amount of packet loss (normal in VoIP) can corrupt a fax transmission, causing pages to fail.
• Jitter: Variation in packet arrival times disrupts the timing-sensitive fax protocol.
• Compression: VoIP codecs compress audio to save bandwidth. Fax tones do not survive compression well.
• T.38 protocol: Some VoIP providers support T.38, a protocol designed to carry fax over IP networks. It works better than standard VoIP but is not universally supported and still less reliable than analogue.

In short: plugging your fax machine into a VoIP adapter and hoping for the best is a recipe for frustration. There are better options.

Option 1: Fax-to-Email Service (Recommended)

A fax-to-email service replaces your physical fax machine entirely. Here is how it works:

• Receiving faxes: You are assigned a fax number (or keep your existing one via porting). Incoming faxes are converted to PDF and delivered to your email inbox.
• Sending faxes: You upload a document to a web portal or email it to a special address, and the service sends it as a fax to the recipient's fax machine.

Benefits:

• No hardware required — no fax machine, no phone line, no paper, no toner.
• Faxes are stored digitally, making them searchable and easy to archive.
• Works from anywhere — send and receive faxes from your laptop or phone.
• More secure than a physical fax sitting in a shared area (important for GDPR and confidential documents).
• Monthly costs are typically £5–£15 per fax number, much less than maintaining a dedicated analogue line.

This is the recommended option for most businesses. It is cheaper, more reliable, and more secure than any hardware-based solution.

Option 2: Analogue Telephone Adapter (ATA)

If you absolutely must keep your physical fax machine — for example, because it is integrated into a specific workflow or required by a regulatory process — an ATA can bridge the gap:

• An ATA is a small box that converts your analogue fax machine's signal to work over a VoIP or broadband connection.
• You plug your fax machine into the ATA, and the ATA connects to your router.
• The ATA handles the analogue-to-digital conversion.

However, be aware of the limitations:

• Fax over an ATA is less reliable than a native analogue line. Failed transmissions are common, especially for multi-page faxes.
• The ATA must support T.38 for the best chance of success, and your VoIP provider must also support T.38 on their end.
• You are maintaining a physical fax machine, paper, and toner for a technology that is fundamentally declining.

An ATA is a short-term workaround, not a long-term solution.

Option 3: Online Fax Platform

Online fax platforms are similar to fax-to-email but offer more features for businesses that send high volumes of faxes:

• Web-based portals for sending, receiving, and managing faxes
• Integration with business software (CRM, document management systems, EHR platforms for healthcare)
• Bulk faxing capabilities
• Audit trails and delivery confirmations for compliance
• API access for developers to build fax into automated workflows

If your business sends hundreds of faxes per month or needs fax as part of an automated process, an online fax platform is the right choice.

What About Fax Numbers?

You can keep your existing fax number in most cases. When switching to a fax-to-email service or online fax platform, ask your provider to port the number. The process is the same as porting any phone number and typically takes 10–20 business days. Your contacts will not notice any change — they fax the same number, and it just arrives in your inbox instead of a machine.

Industry-Specific Considerations

Legal: Many courts and legal processes still accept fax. Fax-to-email services produce PDF records that are equally valid as evidence, and many courts now prefer email or portal submissions anyway.

Healthcare: The NHS and private practices use fax for referrals, prescriptions, and patient data. The NHS has been actively phasing out fax in favour of secure email and NHS systems. A fax-to-email service with encryption meets GDPR requirements for patient data.

Finance: Banks and insurers use fax for signed documents. Digital signature services (DocuSign, Adobe Sign) are increasingly accepted as replacements, and fax-to-email provides a compliant interim solution.

Logistics: Proof-of-delivery faxes and customs documents can move to email or digital platforms. Many shipping companies have already made this transition.

A Practical Recommendation

For the vast majority of businesses, the answer is simple: switch to a fax-to-email service, port your fax number, and retire the physical machine. You will save money, gain convenience, and never run out of toner again.

If you have a niche requirement that genuinely needs a physical fax machine, use an ATA with T.38 support as a bridge while you work toward a fully digital solution.

For more on how the PSTN switch-off affects your wider telephone setup, see our guide to enterprise VoIP and UCaaS solutions in the UK.