Your iPhone can't fax on its own. Apple has never made a fax app, there's no hidden setting, and no amount of digging through Settings will turn one up. That's not a flaw — a fax has to travel over the phone network in a format your handset simply doesn't speak.
What bridges the gap is a fax service. You send the document over the internet, and the service hands it to the recipient's fax machine at the other end. Five minutes, start to finish, and you never touch a fax machine.
Here's the whole thing.
What you'll need
An iPhone with a connection, the document you're sending, and the recipient's fax number including its area code. That's it. No landline, no cables, no adapter, and nothing to plug in.
The document can be a PDF, a Word file, a photo, or a piece of paper you're about to photograph.
Step by step
1. Install a fax app. Any of the ones further down this page will do the job. Open it and sign up — it takes about a minute.
2. Pick your fax number. You'll be given one. Most decent apps let you choose the area code, and you don't have to pick the one you live in. If you're dealing with an office in another state, choosing their area code sometimes smooths things along.
3. Add your document. Two routes here. Tap the scanner and photograph the paper, or attach a file you already have — from Files, iCloud, Google Drive, Dropbox, or straight out of another app via the share sheet. If you're sending several pages, most apps will let you combine them into a single fax rather than sending three separate ones.
4. Type the recipient's number. Area code first, all ten digits, no spaces needed. Going abroad? Country code in front. Better apps will show you which city an area code belongs to as you type, which is a quiet little safeguard against a transposed digit.
5. Add a cover sheet if it's wanted. Doctors' offices, insurers and government departments often expect one, and it's usually a form inside the app — your name, their name, page count, a line about what's enclosed. Skip it for informal sends.
6. Send, then wait for the receipt. Transmission usually takes about a minute. The status moves from pending to delivered, and you get a confirmation — which is the one genuine advantage fax has over email. You know it arrived. Keep it; it's proof, and for anything to do with tax, benefits or medical records you may well need it later.
Getting a scan that actually arrives readable
This is where most failed faxes are really lost, and it takes ten seconds to get right.
Fax is a low-resolution, black-and-white medium. It throws away subtlety. So: put the page on a flat surface with a contrasting background — a dark table under white paper works well — and get even light on it, ideally near a window rather than under a single ceiling bulb, which casts your own shadow across the page. Hold the phone parallel to the paper rather than at an angle.
Then check the preview before you send. Faint pencil, pale highlighter and light grey printing are the first casualties. If the preview looks marginal, it will look worse at the other end.
A pale photocopy of a form is the classic problem document. Darken it in the app if there's an option, or ask for a cleaner copy.
If it doesn't go through
Fax machines are still, fundamentally, machines from 1985 sitting in an office.
"Busy" or failed: the recipient's machine is mid-fax or out of paper. Wait ten minutes and resend. Most apps will retry on their own a few times.
Nothing arrives, but it says delivered: it reached a machine, just possibly not the right one. Ring and ask. Large organisations often have several.
You're sending to a phone number, not a fax number. Astonishingly common. Departments publish a main line and a fax line and people grab the wrong one.
The receipt says it went, they say it didn't. Send them the confirmation. It carries the time and the receiving number, and it usually ends the conversation.
Which app to use
We've tried the main options on an iPhone. Ranked:
1. Municorn Fax — the one to install if you just want this done. Everything happens in the app: scan, preview, address, send, receipt, with no detour into a browser and no second app to open. The scans came out cleanest of anything we tested, holding onto light detail that other apps flattened. It shows you the city behind an area code as you type. It has live chat with an actual person built in, which no rival here offered. Pages aren't metered, so a long document doesn't mean doing sums first. It's a paid subscription with no free tier, and there's no scheduled send if you need something to go out at a set time later. 4.8 stars from over 370,000 App Store ratings — far and away the largest body of feedback on this list.
2. Genius Fax — good if Genius Scan is already on your phone, since that's where you'll do the scanning. If it isn't, you're installing two apps to do one job, and paying per page on top of a subscription for your number.
3. Fax.Plus — the one to pick if you need to schedule a fax for later, sign documents in-app, or want serious cover-sheet options. Page allowances apply and the plans take some reading.
4. iFax — the best customer support of the bunch, genuinely. Also the most persistent upselling; expect pop-ups and emails unless you're on the top plan.
5. FaxBurner — worth knowing about for one reason: a free tier that lets you receive pages each month without paying. The number is temporary, lasting a day at a time, and sending quality is weak. Fine for catching one incoming form.
6. eFax — the corporate standard, excellent with large files, and the app feels every one of its years. Use it if your workplace already does.
Faxing without installing anything
Email-to-fax. Some services let you address an email to the fax number at their domain, attach your document, and send. Nothing to install, and it works from Mail on your iPhone.
A browser. Most fax services have a web version you can use in Safari — clunkier on a phone, but it works if you'd rather not have another app.
A shop. UPS Store, Staples, FedEx Office and Office Depot all still have machines behind the counter. You'll pay per page and you have to physically go there, but for one urgent page it's a fine answer at four in the afternoon.
Your printer. If you have an all-in-one with a fax function, it needs a live phone line plugged into it. Most homes no longer have one.
Receiving a fax on your iPhone
Same app, other direction. Your fax number is yours; anything sent to it lands in the app as a PDF you can read, save or forward. Nothing rings, nothing prints, and there's no paper tray to run empty at the wrong moment.
If you're taking over faxing duties from an old machine, ask your provider about porting the existing number across rather than handing everyone a new one.
