How to Fax a PDF Online — Free and Paid Options

Believe it or not, faxing is still a thing in 2026. Hospitals, law firms, government agencies, and insurance companies all still rely on fax machines for sending documents. The good news is you do not need a physical fax machine anymore. You can fax a PDF directly from your computer or phone using online fax services. Here is everything you need to know.

How Online Faxing Works

Internet fax services (sometimes called e-fax or digital fax) let you send and receive faxes through email, a web interface, or a mobile app. The service acts as a bridge between the digital world and traditional phone lines:

  • You upload your PDF to the fax service
  • The service converts it and sends it over phone lines
  • The recipient gets it on their regular fax machine
  • Incoming faxes arrive in your email as PDF attachments

It works the same as a traditional fax from the recipient's perspective. They have no idea you sent it from your laptop.

Free Online Fax Services

Free fax options exist, but they come with limitations. Most free services restrict the number of pages, add cover page branding, or limit you to a few faxes per day. Still, for occasional use, they get the job done.

FaxZero

FaxZero is one of the most well-known free fax services. It lets you send up to 5 free faxes per day with a maximum of 3 pages each (plus a cover page).

  • Go to faxzero.com
  • Enter the recipient's fax number and your information
  • Upload your PDF file
  • Type an optional cover page message
  • Click Send Free Fax Now

The catch is that free faxes include an ad on the cover page. If that is a dealbreaker for a professional document, consider a paid option.

GotFreeFax

GotFreeFax is similar to FaxZero but without ads on the cover page. It allows up to 2 free faxes per day with a maximum of 3 pages. The interface is basic but functional.

MyFax Free Trial

MyFax offers a 14-day free trial that includes 100 pages of outbound faxing and 100 pages inbound. You do need to provide a credit card to sign up, but you can cancel before the trial ends to avoid charges.

Paid Online Fax Services

If you fax regularly or need a dedicated fax number, paid services are worth the investment. Here are the top options:

eFax

eFax is one of the oldest and most established internet fax services. Plans start around $17 per month and include a dedicated fax number, up to 150 pages per month, and a mobile app.

  • Local or toll-free fax number
  • Send faxes via email, web, or mobile app
  • Digital signature integration
  • Cloud storage for fax archives

HelloFax (by Dropbox)

HelloFax integrates with Dropbox, Google Drive, and OneDrive. Plans start at about $10 per month. It is straightforward to use and great if you already store documents in the cloud.

  • Send faxes from Google Drive, Dropbox, or OneDrive
  • Request signatures on documents
  • No dedicated fax number on the cheapest plan
  • Clean, modern interface

Fax.Plus

Fax.Plus offers a free tier that lets you send up to 10 pages total. Paid plans start around $6 per month for a dedicated number and more pages. It has a solid mobile app and supports scheduled faxing.

  • Free tier available for light use
  • Send from web, email, or mobile app
  • Schedule faxes for later delivery
  • Multiple user accounts for teams

RingCentral Fax

RingCentral is a full business communication platform that includes fax capability. Plans start around $23 per month. Best for businesses that need phone, video, and fax in one platform.

How to Fax a PDF Step by Step

Regardless of which service you choose, the basic process is the same:

  1. Prepare your PDF: Make sure the document is oriented correctly (portrait is standard for faxes). Check that the file size is under the service's limit (usually 20MB or less).
  2. Sign up or visit the fax service: Create an account if required, or use a no-sign-up service like FaxZero for quick one-off faxes.
  3. Enter the fax number: Type the recipient's fax number including the area code. For international faxes, include the country code (for example, 011 44 for the UK).
  4. Upload your PDF: Click the upload button and select your file. Most services accept PDF, along with DOC, DOCX, and image files.
  5. Add a cover page (optional): Enter your name, company, and a brief message for the cover page.
  6. Send: Click send and wait for confirmation. Most services email you a delivery confirmation within a few minutes.

Faxing from Your Phone

Most major fax services have iOS and Android apps that let you fax PDFs directly from your phone. This is handy if you need to fax something while away from your computer.

Recommended mobile fax apps:

  • Fax.Plus: Excellent free tier, clean app
  • iFax: Popular with a simple interface
  • MyFax: Good for business users
  • CamScanner: Scan and fax in one app (great for physical documents)

Tips for Successful Online Faxing

  • Keep pages under 20: Long faxes can time out or fail. If you have a 50-page document, consider splitting it.
  • Use standard fonts and formatting: Fancy fonts, colors, and images may not render well on the receiving fax machine. Stick to standard black text on white backgrounds.
  • Check the fax number twice: Wrong numbers are the most common reason faxes do not go through. Double-check every digit.
  • Send during business hours: Some fax machines are turned off after hours. If your fax fails, try again during the recipient's normal business hours.
  • Watch file size: Large PDFs with high-resolution images may fail. Compress the PDF before sending if it is over 10MB.
  • Include a cover page: Cover pages help the recipient know who the fax is for, especially in offices where multiple people share a fax machine.

Troubleshooting Common Fax Problems

Fax fails to send

  • Verify the fax number is correct
  • Try removing the country code if it is a domestic fax
  • Compress the PDF and try again
  • Try a different fax service

Recipient says fax is blank or garbled

  • Make sure your PDF is not password-protected
  • Convert the PDF to a simpler format and retry
  • Check if the PDF contains scanned images at very low resolution

No confirmation email

  • Check your spam folder
  • Wait a few minutes — some services take up to 15 minutes
  • Log into your account to check the fax status directly

Security Considerations

Faxing is generally considered more secure than email for sensitive documents because faxes travel over phone lines rather than the internet. However, online fax services do process your documents on their servers briefly. If you are faxing highly sensitive information:

  • Choose a reputable service with encryption
  • Look for HIPAA compliance if sending medical documents
  • Check if the service stores your faxes and for how long
  • Delete sent faxes from the service's archive after delivery

Which Service Should You Use?

  • Occasional one-off fax: FaxZero or GotFreeFax
  • Need a dedicated fax number: eFax or Fax.Plus
  • Already use Dropbox or Google Drive: HelloFax
  • Business with team needs: RingCentral Fax
  • Mobile faxing: Fax.Plus or CamScanner

Final Thoughts

You do not need a clunky fax machine sitting in your house to send faxes anymore. Online fax services make it easy to send PDFs as faxes from any device with an internet connection. For occasional use, free services like FaxZero handle the job just fine. If you fax regularly for business, a paid service with a dedicated number is a small investment that pays for itself in convenience.