01
Open your PDF
Choose it from Mail or Files.
First, check which kind of form you have
Some PDFs are fillable: tap a blank and a keyboard appears. Others are flat: the form is just a picture of lines and boxes, often because someone printed it and scanned it. Fillable forms are easy almost anywhere. Flat forms need a tool that lets you place text, dates, and checkmarks wherever you tap.
The free way: Apple's built-in tools
Apple's iPhone guide calls this job filling out forms, signing documents, and creating signatures. Open the PDF from Mail or Files, tap the Markup (pen) icon, and use the text tool to type into blanks. Tap + and Add Signature to sign. On recent iOS versions Apple also has a guide for filling out and signing PDF forms in Preview.
If the form is fillable, one or two pages, and going back to someone on an iPhone or Mac, that's usually enough. Try it first.
Where it gets slow: dates, checkboxes, initials
Markup has no dedicated date tool and no checkbox tool. You type the date into a text box, or draw a check with your finger, then nudge it into place on a small screen. On a flat form there's nothing to snap to, so every line takes a few tries.
Initials are the other time sink. A form that asks for initials on each page means placing the same mark again and again. Markup saves your signature, but not a separate set of initials.
Then there's the file you send back. Markup adds your entries as annotations, a layer on top of the page. Some Windows and Android viewers, and some office systems, don't show that layer. The fix is to flatten the PDF so your text and signature become part of the page. Our guide to signing a PDF on iPhone explains this in more detail.
How to fill out a PDF form with eSign PDF
1
Open the form in eSign PDF
In Mail, tap the attachment, tap Share, and choose eSign PDF. From Files or Safari it's the same Share Sheet. Paper form? Scan it with the camera inside the app.
2
Check the highlighted fields
The app highlights likely signature, name, and date areas. It won't catch every blank on every form, so scroll through and tap anywhere else you need to type.
3
Fill in text, dates, and checkboxes
Use Text for your name, address, and other details. Use Date to insert today's date in the format the form expects, such as MM/DD/YYYY. Use Check to tick boxes. Adjust size so your entries fit the lines.
4
Sign and initial
Draw, type, or import your signature once. Place it on the signature line and add initials on each page that asks for them.
5
Flatten, export, and send
Export the form. eSign PDF flattens it so your entries show on any device, then share it to Mail, Messages, AirDrop, or Files.
Mistakes that get forms sent back
- ✕Leaving the date blank next to the signature when the form asks for one.
- ✕Missing a checkbox on page 3 because you only checked the pages with signature lines.
- ✕Text that runs past the line or covers printed words. Shrink it before you export.
- ✕Sending an unflattened file to an office that uses Windows. They may see empty blanks.
- ✕Uploading a W-9 or medical form with your Social Security number to a random website to fill it.
Flat and scanned forms
Forms from banks, county offices, and older HR systems are often scans. There are no fields, the lines may be crooked, and the text isn't selectable. eSign PDF doesn't turn a scan into a fillable form. It lets you place text, dates, checks, and your signature on top of it, then flattens everything into one clean page. We cover the messiest cases in signing scanned PDFs from banks and government offices.
Tax forms carry extra personal data. If you're completing a W-9 for a client, see signing tax documents on your phone. eSign PDF works on-device: the form isn't uploaded, and there's no account.
What it costs
Apple's Markup and Preview: free. eSign PDF: $59.99 one-time (US), no account. Not sure which you need? Read Apple Markup vs a signing app. Other plans and local prices are shown in the App Store.
FAQ
How do I fill out a PDF form on my iPhone?+
Open the PDF from Mail or Files, tap the Markup icon, and type into the blanks with the text tool. For flat forms, dates, and checkboxes, a form-filling app is faster.
Why can't I type in a PDF form on iPhone?+
The form is probably flat, meaning it has no real fields, often because it was printed and scanned. You need a tool that lets you place text anywhere on the page.
Can I add a checkbox or today's date to a PDF on iPhone?+
In Markup you can type a date or draw a check by hand. eSign PDF has a date tool with formats like MM/DD/YYYY and a one-tap checkbox tool.
Will the person I send the form to see what I filled in?+
If the file is flattened, yes, on any device. Unflattened Markup entries may not show in some Windows or Android viewers.
Does eSign PDF upload my form?+
No. Filling, signing, and flattening happen on your iPhone, with no account. It costs $59.99 one-time (US).