Redact a bank statement before sending it, on a Mac
· 6 min read
To redact a bank statement properly, the hidden details have to be removed from the PDF, not just covered. A black rectangle drawn over an account number usually leaves the number in the file, where anyone can copy it out. On a Mac you can do it well with built-in tools if you accept some trade-offs, and then check the result in under a minute.
Before you redact anything, find out what the recipient actually needs. Some landlords, lenders and agencies accept partial statements; others treat any alteration as a reason to reject a document. Asking first saves you doing it twice.
Decide what to hide and what to leave
A typical request for proof of income or funds needs your name, the bank’s name, the statement period, the deposits that show income, and the balance. What it rarely needs:
- The full account number. Leave the last four digits so the statement can be matched to you; hide the rest.
- Sort codes, routing numbers and IBANs, unless the recipient is setting up a payment to you.
- Transactions unrelated to the question: the pharmacy, the donation, the payment to a family member.
- Card numbers that appear in transaction descriptions.
- Barcodes or QR codes at the edge of the page, which can encode account details.
Keep a list. The most common failure is not a technical one; it is missing the same number printed a second time in a page footer.
Why a black box does not work
A statement downloaded from online banking is almost always a text PDF: the numbers are real, selectable characters. Drawing a filled shape with Markup in Preview places a picture on top of that text. The text is still underneath.
You can see this on your own file. Draw a box over a number, save, then press Command-A on that page and Command-C, and paste into a note. The “hidden” number is usually right there. Why a black box on a PDF does not redact anything goes into the detail.
Redacting with what the Mac already has
Option one: Preview’s redaction tool. Since macOS 11, Preview has a Redact item in the Tools menu, separate from the Markup shapes. Duplicate the statement first (File, Duplicate), choose Tools, Redact, select the text you want gone, then save. What it removes, and what it leaves behind, is covered in redacting a PDF in Preview; read that before relying on it for anything sensitive, and always run the checks further down.
Option two: flatten the pages to images. This is cruder, but easy to reason about. Once the page is a picture, there is no text underneath.
- Open the statement in Preview and draw filled black rectangles over everything on your list.
- Choose File, Export, pick PNG or JPEG, and set the resolution to at least 150 pixels per inch so small print stays readable. Preview exports one page at a time, so repeat for each page.
- Select all the exported images in Finder, open them together in Preview, and choose File, Print, then Save as PDF to combine them into one document.
- Delete the image files once you have checked the result.
The trade-offs are real: the new PDF is not searchable, it is larger, and it looks like a scan. Some recipients will be happier with that than with a text file; others may ask why it is not the original. If you have a paper statement, scanning it and covering the details before export follows the same logic, with the caveats in redacting photos and scans inside a PDF.
Check the file before you send it
Whatever method you used, do these checks on the copy you are about to send, not the working file.
- Search for it. Open the PDF, press Command-F, and type the last several digits of the account number you removed. Then try the card number and one of the redacted payee names. No results is what you want.
- Select everything. Command-A, Command-C on each page, paste into a plain note, and read it through.
- Look at the thumbnails. Show the sidebar in Preview. A stale page thumbnail can still show the original.
- Check the file details. Tools, Show Inspector in Preview shows the title and author fields; a bank’s file sometimes carries your name or account reference there. Removing metadata from a PDF covers clearing it.
- Rename the file. A file named after your account number undoes all of the above.
How to check whether a PDF was really redacted has a longer version of this list.
When you do this more than once
If you regularly send statements, pay slips or tax documents, it helps to have a tool built for the job. Basalt is a Mac PDF app whose redaction removes content rather than covering it: text under a mark is excised, images under a mark are destroyed and re-encoded, and metadata, attachments, hidden layers and old thumbnails are stripped. You review every mark before applying. Before any file is written, its verifier re-opens the export with an independent parser and checks the redacted strings are absent; if a check fails, no file is written. The original statement is never modified, and the engine that opens documents has no network access, which is a sensible property for financial records. Its Inspect tool also shows what a PDF still hides before you start. It is free for 24 hours with every tool, then $29 for a lifetime license.
Questions
Is it legal to redact my own bank statement? Removing private details from a copy of your own statement is common and generally fine. What matters is not misrepresenting anything, such as altering amounts or balances. If a recipient requires an unaltered statement, send it through the channel they specify instead.
Can I just take a screenshot of the statement instead? A screenshot is an image, so covered details are gone from it. It is lower resolution than the export method above, and many recipients will not accept screenshots as documents, so ask first.
What if the bank statement is password protected? Open it with the password you were given, then save or export a copy to redact. Removing the password from a PDF you own covers the steps.