How to fill in a PDF form — even one that isn’t fillable

Application forms, tax forms, rental agreements, school consent slips: a great many of them arrive as PDFs with a request to “complete and return”. Printing, filling in by hand and scanning works, but it is slow and the result is often hard to read. Most of the time you can fill the form in on screen instead. How depends on what kind of PDF you have been sent.

First, find out what kind of form it is

Open the PDF and click inside one of the boxes you need to fill in. One of three things happens:

• A cursor appears and you can type. The form has real fields. This is the easy case, covered next.
• Nothing happens. The boxes are just lines printed on the page, or the whole form is a scan. It is not fillable, but you can still add text on top — see further down.
• You see a message such as “Please wait…” or “this document requires a newer viewer”. The form was built with an older Adobe technology called XFA, which only Adobe's own reader can display. Open it in the free Adobe Acrobat Reader on a computer.

Filling in a form that has fields

You do not need special software. The PDF viewers built into Chrome, Edge and Firefox all let you type into form fields, tick boxes and choose from drop-down lists. So do the free Adobe Acrobat Reader and Preview on a Mac. On phones, recent versions of the Files app on iPhone and the PDF viewer in Google Drive on Android can fill simple forms.

1. Open the PDF and click into the first field.
2. Press Tab to move to the next field. Forms are usually set up so Tab follows the order of the questions.
3. Watch for fields that check what you type, such as dates or numbers. If a field refuses your entry, it usually wants a particular format — try the one shown in the label, such as DD/MM/YYYY.
4. Save or download the filled-in copy. In a browser, use the download or save button in the PDF toolbar rather than the browser's own menu, so the answers are saved into the file.
5. Close the file and open the saved copy to check that every answer is still there.

Filling in a form that has no fields

When the boxes are only printed lines, you add text on top of the page instead:

• Adobe Acrobat Reader (free) has a Fill & Sign feature that lets you click anywhere on a page and type.
• Preview on a Mac has a text tool in its Markup toolbar that does the same.
• If neither is available, printing, writing by hand and scanning is still a valid route. Scan in greyscale at 200–300 dots per inch so the handwriting stays legible.

Whichever you use, line the text up with the boxes and zoom in to check nothing overlaps the printed labels. Forms that will be read by a machine are less forgiving than a person.

Lock your answers before you send

A filled-in form still has live fields. Anyone who receives it can click into a field and change an answer, and some PDF viewers display form fields badly — answers can look wrong or vanish entirely on the other person's screen. Flattening fixes both. It paints each answer onto the page as ordinary content and removes the interactive field.

1. Open Flatten PDF Form and add your filled-in copy.
2. Check the list of fields it found, to be sure you loaded the right document.
3. Press Flatten form and download the locked copy.

Keep the editable version for yourself in case something needs to change, and send the flattened one. Flattening cannot be undone.

Signing the form

Sign after flattening, so nothing on the page can change once your signature is on it. Sign PDF lets you draw your signature with a finger, stylus or mouse and place it on the signature line. For more on what a drawn signature does and does not prove, see how to sign a PDF without printing it.

Sending the form with supporting documents

Many applications ask for the form plus copies of documents — a payslip, a proof of address, a certificate. If they want a single file, combine everything with Merge PDF. Flatten the form first: merging carries pages across but not form fields, so an unflattened form can lose its answers in the merged file.

A checklist before you press send

• Every required field is filled in, including the ones on later pages.
• Dates, reference numbers and your name are spelled exactly as on your documents.
• The saved copy shows your answers when reopened — ideally check it in a second viewer.
• The form is flattened and signed, in that order.
• The file name says what it is, such as surname-application-form.pdf.

A note on privacy

Forms are full of personal details: addresses, dates of birth, bank and passport numbers. Many “fill PDF online” websites upload the document to their servers to do the work. Filling the form in your own PDF viewer and flattening and signing it in the browser keeps those details on your device until you choose to send them.