Free PDF comments: mark up documents without paying for Acrobat

You get a PDF to review — a draft contract, a flyer design, an annual report. And because “you need paid Acrobat for PDFs,” people write their feedback into an email instead: “on page 4, third paragraph, the second sentence should read…” The recipient then has to puzzle out what goes where. But commenting on a PDF has been free for a long time: highlighting text and adding notes is handled by the free Adobe Acrobat Reader, the Edge browser, and Preview on Mac — and the feedback travels right inside the file, exactly where it belongs.

How to do it

Acrobat Reader (free, Windows and Mac):

1. Open the PDF and choose Comment from the tools — a toolbar appears with a highlighter, a sticky note, underlining, and other annotation tools.
2. Select text to highlight it, or drop a sticky note anywhere and write your comment. You can reply to other people's comments — the file grows a normal threaded discussion, much like in Google Docs.
3. Save and send it back — every comment lives inside the file, and the recipient sees a tidy list they can work through item by item.

A no-install quick option: in a PDF opened in Edge, select text and pick a color from the toolbar to highlight it; right-click a selection to add a comment. On a Mac, Preview works too — its annotation tools include a highlighter and text notes.

And if your team lives in Google Workspace, you don't even need to send files back and forth: a PDF uploaded to Google Drive can be commented on right in the preview — select a spot, add a comment, and pull in colleagues with an @ mention, just like in Docs. Everyone then comments on one shared copy.

A typical scenario

A lawyer sends a client a draft contract. Instead of three screens of email (“I disagree with Article IV…, add to Article VII…”), the client opens the PDF in the free Reader, highlights the disputed spots, and attaches a note to each one explaining what to change and why. The lawyer sees every comment right next to the sentence it concerns, replies to unclear ones directly in the file — and nothing gets lost translating between an email and a document.

What you get out of it

Comments anchored exactly to the spot they concern — no more puzzling out “which paragraph did she mean.” The review cycle gets shorter because both sides work on one file, and a written record of every point stays together in the document — which comes in handy months later too, when someone's trying to remember who requested which change.

Pro tip

If a PDF asks you for a signature instead of comments, you don't need to print it: on a Mac, Preview inserts one, and elsewhere you can sign directly in the browser.