Find out whether the form is fillable
Open the PDF in your browser and click into the first answer box. If a cursor appears and you can type, the form has fillable fields — the author built it to be completed on screen. Fillable fields are often highlighted in a light colour, and pressing Tab moves you from one to the next.
If clicking does nothing, the form is flat. Its boxes and lines are printed onto the page like any other graphic, which is common for forms that started life as a scanned paper document or a word-processor file exported to PDF. A flat form can still be filled on screen; you just place text on top of the page rather than typing into it.
Some forms are a mixture: a few fields are fillable and the rest are not, or a single section was added later as flat content. Check the whole form, not just the first page, before you choose a method. Discovering on page four that the signature block is flat is easier to deal with at the start.
Fill a fillable form in your browser
The PDF viewers built into Chrome, Edge and Firefox can type into fillable fields, so you often need nothing else. Open the file in the browser, click each field and type your answer. Drop-down lists and checkboxes work too, as long as the form author created them as real fields.
Watch for fields that are too small for the answer. A fillable field may shrink the text to fit or cut it off without warning, depending on how it was set up. If an address or a description disappears past the edge of its box, shorten it, or check whether the form provides a continuation section.
Do not rely on the open tab as your record. Fillable answers live in the browser’s view until you save or download the file, and closing the tab can discard them. Save as you go — section five covers making sure the saved copy actually contains what you typed.
Fill a flat form by adding text on top
For a flat form, open Edit PDF and use the text tool to place a box over each answer area. Set the size and colour so the text fits inside the printed box and reads clearly — black or dark blue at a size close to the form’s own labels usually looks most natural.
Edit PDF adds new content on top of the page; it does not change the form’s own printed text. That is exactly what you want for form-filling, because the original questions stay untouched and your answers sit where a pen would have gone. Everything happens in your browser, so personal details such as your address, date of birth or ID numbers are not uploaded anywhere.
Work through the form in order and zoom in while placing text. Lining answers up with printed lines is fiddly at full-page view and easy when magnified. A form that looks neatly completed is quicker for the recipient to process, and less likely to be returned because something was unreadable.
Ticks, dates and signatures
On a flat form, a checkbox is just a printed square. Mark it by placing a single “X” as text, or by using the draw tool for a tick — whichever looks clearer at the size of the box. Be consistent throughout the form so that a reviewer can tell at a glance which options you selected.
Write dates in the format the form asks for. Many forms print a hint such as DD/MM/YYYY beneath the field, and a date in the wrong order is a classic reason for a form to be rejected, particularly across countries that write dates differently. When no format is given, writing the month as a word avoids any ambiguity.
For the signature, use Sign PDF to draw, type or upload your signature and place it on the signature line, or add a signature image with Edit PDF. The guide to signing a PDF covers making a drawn signature look natural and placing it accurately.
Save a copy that keeps your answers
Save or download the completed form under a new name — for example, the original filename with your surname and the date. Keeping the blank form separately means you can start again cleanly if you need to, and a descriptive filename tells the recipient whose form it is.
Then close the saved file and open it again. This is the most important check in the whole process: it confirms your answers were written into the file rather than only displayed in the tab. Answers that vanish on reopening were never saved, and the recipient would have received a blank form.
Open the saved copy in a second viewer if you can, such as a different browser or a desktop PDF reader. Fillable answers occasionally display in one application and not another, depending on how the form was built. Seeing them in two viewers is good evidence the recipient will see them too.
Check the form before you send it
Read every page of the saved copy as if you were the person processing it. Look for answers that spill outside their boxes, missed required fields, inconsistent dates and a signature on the right line of the right page. Correcting a form after it has been submitted is usually far more work than a careful read now.
Check the file size if the form goes through an upload portal. Adding a signature image or several pages of text rarely makes a form large, but a scanned form can be several megabytes to begin with. If the portal rejects it, the upload troubleshooting guide covers reducing it without making it unreadable.
Keep your completed copy. A form you filled on screen is easy to lose track of, and it is your only record of what you declared, when, and how you signed it — useful if a question arises later or if you need to complete a similar form next year.
Open Edit PDFAdd text, ticks and a signature to a flat form — nothing uploaded.
Open Edit PDF →Frequently asked questions
Why can't I click into the boxes on the form?
The form is flat: the boxes are part of the page design, not interactive fields. Add text boxes on top of them with a PDF editor instead of trying to type into the page.
Can the recipient change my answers after I send the form?
Answers in fillable fields can usually be edited by anyone with a PDF editor. Text added on top of a flat form is harder to change but not impossible. Keep your own copy as a record.
Is my information uploaded when I fill the form?
Not with your browser’s built-in viewer or with PDFNest’s Edit PDF, both of which work on your device. Check any other online form-filling service before entering personal details.