# Fax to email and email to fax: send and receive faxes without a fax machine > Fax to email turns your inbox into your fax machine. Here is how to set up both directions with Voxbi so your team can send and receive faxes from wherever they already work. Public AI-agent markdown version of [this guide](https://www.voxbi.com/blog/fax-to-email) on the Voxbi website. HTML page: https://www.voxbi.com/blog/fax-to-email Markdown page: https://www.voxbi.com/blog/fax-to-email.md - Published: 2026-07-20 - Category: Voxbi setup guides - Author: Voxbi team (Communication features) --- Fax to email turns your inbox into your fax machine. Incoming faxes land as a PDF in your email, and you send outgoing faxes as an email attachment. No paper, no toner, no dedicated line humming in the corner. This guide walks through setting up both directions with Voxbi so your team can send and receive faxes from wherever they already work. If your business still deals with the occasional fax (and in healthcare, legal, and public-sector work, plenty still do), this is the modern, paperless way to handle it. You keep the fax number your contacts already have, but the machine disappears. Fax to email is available as part of the wider [Voxbi features](https://app.notion.com/features) suite alongside calling, messaging, and more. ## What you need before you start The fax option is provisioned on your account, so a few things need to be in place first. Order the fax option through your Voxbi setup, and you will receive: - **A fax number** for receiving faxes (this powers fax to email). - **A personal fax key** for sending faxes (this powers email to fax). It looks like `fk: xxxxxx-xxxxxxxxx`. - **A destination email address** where incoming faxes should be delivered. Once those three items are set, both directions are ready to use. There is nothing to install on your computer, and no hardware to configure. ## Fax to email: receive faxes as a PDF in your inbox This is the receiving direction. Every incoming fax is automatically converted to a PDF and emailed to the address you chose. 1. Your fax number is provisioned for you when you order the fax option. 2. You define the destination email address that should receive incoming faxes. 3. From then on, any fax sent to your number arrives as a PDF attachment in that inbox. That is the whole flow. Nothing to click when a fax comes in: it simply shows up as an email with the document attached, ready to read, forward, or file. If your team uses shared inboxes, you can point the destination at a shared address so more than one person receives incoming faxes automatically. ## Email to fax: send a fax straight from your email This is the sending direction. You compose a normal email, attach the document, and it goes out as a fax. The recipient receives it on their fax machine or fax-to-email service, with no indication that it was sent from email. 1. Open your email program and start a new email. 2. In the **To** field, enter the fax number as the recipient in the format `+[country dialling code][fax number]@ufax.eu`. For example, a fax to a Luxembourg number would be addressed to `+35220333320@ufax.eu`. 3. Attach the document you want to fax as a **PDF** (see the limits below: one attachment, up to 5 pages, A4). 4. In the email body, add your fax key on its own line: `fk: xxxxxx-xxxxxxxxx`. 5. Send the email. You will automatically receive a delivery report confirming whether the fax went through. ![Email compose window showing a fax recipient address at [ufax.eu](http://ufax.eu) in the To field and the fax key entered in the email body](https://www.voxbi.com/assets/blog/fax-to-email/fax-to-email-compose-window.webp) The example above shows the two things that matter: the recipient address ending in `ufax.eu`, and the fax key in the body of the message. Both must be present or the fax will not send. ## Sending limits to keep in mind Email to fax has a few constraints. If a fax does not go through, this list is the first place to check. - **One PDF attachment per email.** Combine multiple documents into a single PDF first. - **Maximum 5 pages** per fax. - **A4 format only.** - **The fax key must be in the email body.** Without it, the fax will not send. If you regularly need to send documents longer than 5 pages, split them into separate emails of up to 5 pages each. Each split sends as its own fax transmission and arrives in sequence at the recipient. ## Still need a physical fax machine? Most teams are happy sending and receiving through email. But if you have a workflow that genuinely needs a physical device (a machine that scans and dials the old way), an analog converter can be provided on request so a traditional fax machine keeps working over your Voxbi setup. Ask during setup if this applies to you. ## How fax to email compares to a traditional fax line A dedicated fax machine and phone line requires hardware, consumables (toner, paper), and someone to physically manage the machine. Fax to email removes all of that:
Traditional fax Fax to email
Hardware required Yes No
Paper and toner Yes No
Accessible remotely No Yes (any device with email)
Documents stored automatically No Yes (PDF in your inbox)
Works with your existing email No Yes
For teams working across multiple locations or remotely, fax to email is the practical default. Documents arrive in your inbox the moment they are sent, and you can forward, archive, or respond without printing a thing. ## Troubleshooting **My fax did not send.** Check the three most common causes: the fax key is missing or mistyped in the email body, the attachment is not a PDF, or the document is over 5 pages or not A4. Fix the issue and resend. The delivery report you receive back will usually say what went wrong. **The recipient address was rejected.** Make sure the address follows the exact format `+[country dialling code][fax number]@ufax.eu` with the leading `+` and no spaces. A missing dialling code is the usual cause. **I am not receiving incoming faxes.** Confirm the destination email address on file is correct and check the spam or junk folder, since a PDF from an automated sender can occasionally be filtered. If nothing arrives after checking those two things, the fax number setup can be verified with support. **I need to fax more than 5 pages.** Split the job into separate faxes of 5 pages or fewer, each sent as its own email. ## Frequently asked questions **Do I need a fax machine to use fax to email?** No. Faxes arrive as PDFs in your email inbox, and you send faxes as email attachments. No hardware, no dedicated fax line, and no paper required. **How do I send a fax from my email?** Compose a new email, put the fax number in the To field as `+[country dialling code][fax number]@ufax.eu`, attach your document as a single PDF, and write your fax key as `fk: xxxxxx-xxxxxxxxx` in the email body. Send it, and you will receive a delivery report confirming whether it went through. **What is the fax key and where do I put it?** The fax key is your personal sending credential, formatted `fk: xxxxxx-xxxxxxxxx`. You receive it when the fax option is provisioned on your account. It must appear on its own line in the body of the email you send, or the fax will not go through. **What file formats and sizes are supported for sending?** Send one PDF attachment per email, up to 5 pages, in A4 format. If you have several documents to send together, merge them into a single PDF first. To send more than 5 pages total, split them across multiple emails. **Can I keep my existing fax number?** Yes. Fax to email works with a fax number provisioned on your Voxbi account, and all incoming faxes to that number are delivered to your chosen email address as PDFs automatically. **Can multiple people receive incoming faxes?** Yes. Point the destination address at a shared or group email inbox and everyone in that inbox will receive each incoming fax. This works with any email provider that supports shared inboxes. ## Ready to go paperless with fax? Fax to email and email to fax are part of the wider Voxbi communication toolkit. Explore the full set of [Voxbi features](https://app.notion.com/features) to see how calling, messaging, and faxing come together in one place, and if your team also sends texts, take a look at our guide to the [business SMS gateway](https://app.notion.com/blog/business-sms-gateway). Ready to set up fax on your account? Get in touch and we will provision your fax number and key.