Redacting a PDF on iPhone or Mac
Published October 27, 2026
On a Mac, Preview has a redaction tool; Apple's Preview guide lists it from macOS Big Sur (version 11) on. On iPhone and iPad, Apple's help pages for Markup describe adding text, shapes, drawings and signatures to a PDF and do not mention redaction, so a black shape drawn with Markup is not known to remove anything underneath. Either way, check the finished file before sending it. This is general information, not legal advice.
On a Mac: Preview's redaction tool
Preview's Markup toolbar has a Redaction Selection tool. Apple's current guide describes it as removing selected text from view, and says you can change a redaction while you edit, but once you close the document it becomes permanent. The Big Sur edition of the guide also suggested redacting a duplicate, to keep the original.
What Apple's guide says, and leaves out:
- It works on the text you select. The guide does not describe searching for a pattern such as a Social Security number, so you find each one yourself, on every page.
- The table of contents. Apple notes that if the PDF has a table of contents, entries in it that link to redacted text are not removed.
- Redaction is not the Shapes tool. A filled black rectangle from Shapes is an annotation on top of the page. The text under it stays.
- Flattening is not removal. Apple says that to flatten annotations so they cannot be edited, you choose File > Print, then Save as PDF. That stops a box from being moved. It does not by itself remove text under the box.
- Metadata. The guide does not say the redaction tool removes document properties such as Title or Author.
Checking a Preview redaction
- Close the document so the redaction becomes permanent, then open it again.
- Search for the word or number you removed.
- Select across the black area, copy, and paste into TextEdit. Nothing should paste.
- Look at the document's properties for a name or number.
- Search the rest of the file for other copies of the number, since you redacted only what you selected.
On iPhone and iPad: Markup
Apple's iPhone help on Markup covers writing, drawing, and adding text, shapes, stickers and signatures to documents, and its Markup support article mentions adding a signature to a PDF. None of these pages mentions redaction, and none says whether a shape added to a PDF removes the text under it. Shapes in PDFs generally sit on top of the page, so the cautious reading is that the text is still there until a check shows otherwise.
Checking on a phone is awkward. If you can open the saved PDF and select or search the covered text, it is still in the file. A computer makes it easier: copy across the box and paste, search, and read the properties, or run the free leak check.
The browser route
Browser tools are a third route, and on a Mac they add what Preview leaves out. letsgoPDF's Smart Redact, free and without an account, finds email addresses, phone numbers, Social Security numbers, card numbers and IBANs and deletes them, working in the browser. batesstamp.com's free redaction tool has you draw boxes and then renders every page as a 300 DPI image, so nothing under a box survives, though nothing in the file can be searched afterward either. The free redaction guide lists more, including which ones upload your file.
What neither Preview nor Markup does
- Search a whole file, or a set of files, for Social Security, account, routing and card numbers in their different formats.
- Keep the last four digits of a number, the form federal court rules allow; see redacting SSNs and account numbers in court filings.
- Remove metadata, comments and attachments, as far as Apple's guides say.
- Bates-number the pages of a production; see Bates numbering without Acrobat.
For a single bank statement, Preview plus a check is often enough (see redacting a bank statement). For a stack of PDFs, selecting each number by hand is where mistakes come from.
BatesNumbering.app runs in your browser: it looks for those numbers across every file, lets you keep the last four digits, burns the boxes into only the pages that have them, removes metadata, comments and attachments, and runs the leak check on the output.
Common questions
Can you redact a PDF on a Mac without Adobe?
Yes. Preview has a Redaction Selection tool in its Markup toolbar, and Apple's guide lists it from macOS Big Sur on. Apple says the redaction becomes permanent once you close the document.
Can you redact a PDF on an iPhone?
Apple's iPhone help for Markup describes adding text, shapes and signatures, not redaction, and does not say a shape removes the text under it. A Mac or a browser-based redaction tool is the other route; check the result either way.
Does Preview remove metadata when it redacts?
Apple's guide does not say it does. Look at the document's properties after redacting, or run a check that reads the metadata.
Why can I still see redacted text in the table of contents?
Apple's Preview guide says table of contents entries that link to redacted text are not removed. Check the outline and bookmarks after redacting.
Redact and Bates-number a set of PDFs in one pass →Or check a PDF for numbers left in it, free →
More guides: What is Bates numbering · Bates numbering without Acrobat · Bates number format and examples · Bates numbering a discovery response without a lawyer · Exhibit numbers vs Bates numbers · How to redact a PDF for free · Redacting SSNs and account numbers in court filings · Redacting a bank statement · Why black box redactions fail · A document production index · Rolling productions · Responding to a request for production · Bates and redaction tools compared · batesstamp.com alternatives · RedactifyAI alternatives · Adobe Acrobat alternatives for Bates and redaction