By David Thompson · Published November 11, 2025 · Updated June 8, 2026 · 9 min read
Quick Answer: HP OfficeJet and OfficeJet Pro printers have a built-in fax port that works with a standard phone line. Load your document, press Fax on the control panel, dial the number, and press Send. No phone line? Use HP Smart Mobile Fax or mFax.to instead — both send faxes over Wi-Fi.
Your HP printer probably can fax. The question is which method makes sense for your setup.
If you have an active landline, the built-in fax hardware on HP OfficeJet printers works reliably and costs nothing extra. If you dropped your landline — like most households did years ago — you still have two clean options: the HP Smart app's Mobile Fax feature, or an online fax service that works from any device.
This guide covers all three methods in plain steps, plus how to troubleshoot the most common HP fax problems.
Which HP Printers Can Send Faxes?
Not all HP printers include fax hardware. Here's a quick breakdown by product line:
| HP Product Line | Fax Capability | Notes |
|---|---|---|
| OfficeJet Pro (8025e, 9025e, 9135e, etc.) | Yes — built-in | Most reliable for faxing; designed for business use |
| OfficeJet (standard series) | Yes — built-in | Includes RJ-11 port and fax software |
| ENVY | Rarely | Some ENVY models have fax; check your model spec sheet |
| DeskJet | No | Home-oriented; no fax hardware included |
| LaserJet (most models) | No | Some LaserJet MFP models include fax; verify with HP |
How to check your specific model: Look at the back of the printer. If you see two small phone-jack-sized ports labeled 1-LINE and 2-EXT, your printer has fax hardware.
No fax port on your HP printer?
Skip to Method 3. You can still send a fax from your computer or phone using mFax.to — no printer fax hardware required. Over 5 million people use it as a faster alternative to physical fax machines.
Method 1: Fax from HP Printer Control Panel (Phone Line Required)
This is the traditional method using your HP printer's built-in fax hardware. You need an active analog phone line (landline). VoIP lines like Vonage or magicJack often cause issues — see Troubleshooting below.
What You Need
- HP OfficeJet or OfficeJet Pro printer with fax capability
- An active analog phone line
- The RJ-11 phone cord (usually included in the box)
- The document you want to fax (paper or digital file)
Step 1 — Connect the Phone Line
Connect the phone cord to the 1-LINE port
Look at the back of your HP printer. You'll see two small ports:
- 1-LINE — connect your wall phone cord here
- 2-EXT — for an optional telephone handset on the same line
Plug one end of the RJ-11 phone cord into the 1-LINE port on the printer. Plug the other end into your telephone wall jack.
Important: Using the wrong port is the #1 cause of HP fax failures. The cord must go into 1-LINE, not 2-EXT.
Step 2 — Configure Basic Fax Settings
Set your fax header and rings-to-answer
Before your first fax, configure the basics on the printer's touchscreen:
- On the control panel, tap Setup (the gear icon)
- Select Fax Setup → Basic Fax Setup
- Set Fax Header — enter your name or company name and fax number (required by FCC regulations)
- Set Rings to Answer — how many rings before the printer picks up (2–4 rings is typical)
- Set Auto Answer to On if you want to receive incoming faxes automatically
To verify everything is connected correctly, go to Setup → Tools → Run Fax Test. The printer will print a test report confirming the phone line is detected.
Step 3 — Load Your Document
Load the document into the ADF or flatbed
HP OfficeJet printers have two ways to load a document:
- Automatic Document Feeder (ADF) — the slot on top. Use this for multi-page documents. Load pages face-up in the correct orientation, and adjust the paper guides to fit.
- Scanner glass (flatbed) — lift the lid and place one page face-down. Use this for bound books, photos, or fragile documents.
The ADF is faster for multi-page faxes. The flatbed gives better image quality for single pages.
Step 4 — Dial and Send
Enter the fax number and press Send
- On the control panel, tap Fax
- Use the keypad to dial the recipient's fax number
- For local numbers: dial 10 digits (area code + number)
- For long distance: dial 1 + 10 digits
- For international: dial 011 + country code + number
- Tap Black to send a black-and-white fax, or Color to send in color
- The printer dials, connects, and transmits. You'll hear the modem handshake tones.
- A confirmation page prints when the fax is successfully delivered
Confirm delivery
HP printers print a fax confirmation report after each send. If it shows "OK" or a check mark, the fax was delivered. If it shows an error code, see the Troubleshooting section below.
Receiving Faxes Automatically
With Auto Answer turned on, your HP printer answers incoming fax calls and prints them automatically. To turn this on:
- On the control panel, tap Fax → Settings → Preferences
- Set Auto Answer to On
If you share the phone line with a voice telephone, set Rings to Answer to 4 or more to give yourself time to answer voice calls first.
Method 2: HP Smart App — Mobile Fax (No Phone Line)
The HP Smart app includes a Mobile Fax feature that sends faxes over the internet. No phone line needed. No printer fax hardware needed. Your HP printer just needs to be connected to Wi-Fi.
Limits: Up to 50 pages or 20 MB per fax. Send-only — you cannot receive incoming faxes with Mobile Fax.
How to Set Up HP Smart Mobile Fax
Install the HP Smart app and sign in
Download the HP Smart app from the App Store, Google Play, or the Windows Microsoft Store. Sign in or create a free HP account.
Enable the Mobile Fax tile
In the HP Smart app home screen, tap Personalize Tiles (or the + icon). Toggle on Mobile Fax and save. The Mobile Fax tile will appear on your dashboard.
Enter your sender details
The first time you use Mobile Fax, the app asks for your name and a phone number. This is used as your fax sender ID on the recipient's end.
Select your document and send
- Tap the Mobile Fax tile
- Tap Add Document — choose a file from your device, scan with the camera, or use a photo
- Enter the recipient's fax number (include country code for international)
- Optionally add a cover page with a note
- Tap Send Fax
The app sends the document over the internet to the recipient's fax machine or online fax service.
Mobile Fax cannot receive faxes
HP Smart Mobile Fax is send-only. If you need to receive faxes without a phone line, use an online fax service like mFax.to which gives you a dedicated fax number for both sending and receiving.
Method 3: Use mFax.to — Fax Without Printer Hardware
If your HP printer doesn't have a fax port, or you want a simpler setup with better delivery rates and the ability to receive faxes, an online service is the cleanest solution.
mFax.to works on any device — phone, laptop, or tablet — and doesn't require any printer hardware or phone line.
How to Send a Fax with mFax.to
- Go to mFax.to in your browser (or download the app)
- Upload your document — PDF, Word doc, or photo
- Enter the recipient's fax number (with area code)
- Add an optional cover page note
- Click Send Fax
- Receive a delivery confirmation in your inbox
The service handles the transmission over its own fax infrastructure with a 98% delivery success rate and sends you a confirmation receipt.
mFax vs. HP Printer Built-In Fax: Which Should You Use?
| HP Printer Built-In Fax | HP Smart Mobile Fax | mFax.to | |
|---|---|---|---|
| Phone line required | Yes | No | No |
| Receives faxes | Yes | No | Yes (dedicated number) |
| Works without printer | No | No | Yes |
| Delivery confirmation | Printed report | In-app | Email receipt |
| HIPAA compliant option | No | No | Yes (mFax Business) |
| Cost | Free (landline cost) | Free (limited) | Pay-per-use / subscription |
For occasional personal faxes, the built-in hardware or HP Smart are both fine. For business use, healthcare, or regular faxing without a landline, mFax Business gives you a dedicated virtual fax number, HIPAA compliance, and team access starting at about $9/mo (billed annually). Unlike most providers' rigid tiers, you build your own plan — choose the exact seats and pages you need with a live calculator and pay only for what you use.
HP Fax Settings Worth Configuring
Before relying on your HP fax regularly, tweak these settings from the control panel (Setup → Fax Setup):
| Setting | Where to Find It | Recommended Value |
|---|---|---|
| Fax Speed | Advanced Fax Setup | Start at Medium; drop to Slow if faxes fail |
| Error Correction Mode (ECM) | Advanced Fax Setup | On by default; turn Off if line quality is poor |
| Fax Header | Basic Fax Setup | Your name/company + fax number (FCC required) |
| Rings to Answer | Basic Fax Setup | 2–4 rings for dedicated fax line; 4–6 for shared voice line |
| Backup Fax Reception | Advanced Fax Setup | On — saves received faxes in printer memory as backup |
| Dial Type | Basic Fax Setup | Tone (default); switch to Pulse only if your local exchange requires it |
Troubleshooting Common HP Fax Problems
"No Dial Tone Detected"
Cause: Phone cord is in the wrong port, or the wall jack has no active phone service.
Fix:
- Make sure the cord is plugged into the 1-LINE port, not 2-EXT
- Plug a regular phone into the same wall jack and listen for a dial tone
- If no dial tone: contact your phone provider — the line may be inactive
- If you have DSL: you need a DSL filter between the wall jack and the printer
Fax Sends But Recipient Never Receives It
Cause: Wrong number format, recipient's machine was busy, or line quality issues.
Fix:
- Double-check the fax number — include area code and any required access codes
- Try sending again (busy signals are common on standalone fax lines)
- Reduce fax speed: Setup → Advanced Fax Setup → Fax Speed → Slow
- Turn off Error Correction Mode to improve success on noisy lines
"Communication Error" on Confirmation Page
Cause: VoIP phone service interference, or line noise.
Fix:
- HP's built-in fax hardware is designed for analog phone lines. VoIP services (Vonage, magicJack, Google Voice, most cable company phone services) often cause communication errors.
- Solution: Use Method 2 or 3 above — HP Smart Mobile Fax or mFax.to both bypass the phone line entirely.
Faxes Print With Black Lines or Poor Quality
Cause: Dirty scanner glass or low ink.
Fix:
- Wipe the flatbed glass and the ADF glass strip with a lint-free cloth
- Check ink levels — low ink affects print quality on received faxes
- Adjust fax resolution: Setup → Fax Setup → Default Resolution → Fine or Superfine
Run the built-in fax test
Go to Setup → Tools → Run Fax Test on your HP printer. It checks the phone line, dial tone, fax port, and modem in one step and prints a detailed diagnostic report.
HP Fax on DSL or VoIP: What You Need to Know
DSL Internet + Phone Line: If your internet service comes through the same phone line as your voice service (common with older DSL plans), you need a DSL filter on every phone device — including your HP printer. Plug the filter into the wall jack, then connect the printer to the filter. Without a filter, DSL signals interfere with fax tones and cause failures.
VoIP Phone Service (Vonage, magicJack, cable company phone): These services digitize voice calls, which is incompatible with the analog signaling fax machines use. You may get faxes to work at lower speeds (9,600 bps), but it's unreliable. The better solution is to skip the phone line entirely and use mFax.to or HP Smart Mobile Fax for internet-based transmission.
Fiber Optic (FIOS, AT&T Fiber): Similar to VoIP — fax over fiber is unreliable without special adapters. Online fax services are the practical solution.
Send Your Fax Now
If your HP printer has a fax port and you have an active landline, follow Method 1 — it's the most straightforward. If you've cut the cord or your printer doesn't include fax hardware, mFax.to lets you send and receive faxes from any device in under 2 minutes.
Over 5 million users trust mFax to deliver faxes reliably — with a 98% delivery success rate and confirmation receipts for every send.
For business teams that need a dedicated fax number, HIPAA compliance, and shared access, mFax Business starts at about $9/mo and replaces your physical fax machine entirely.