How do I watermark a copy of my ID or passport before sending it?

Landlords, letting agents, employers, recruiters, hotels, car-hire desks and many online services ask for a copy of your passport, ID card or driving licence. Once you send it, you no longer control where it is stored, who can open it, or what happens to it if their inbox is ever breached.

A clean, unmarked copy of an identity document is exactly what someone needs to open an account in your name. A watermark does not stop a copy being stolen. It does make a stolen copy much less useful, and privacy regulators in some European countries recommend it for exactly that reason.

What the watermark should say

Three things, kept short:

• Who the copy is for: the company or person receiving it.
• What it is for: a rental application, pre-employment check, hotel check-in.
• The date you sent it.

For example: *Copy for Northside Lettings (rental application only) May 2026.* Anyone later trying to use that copy for something else has to explain why it says otherwise.

Do not put your ID number, date of birth or signature in the watermark. The point is to add context, not more personal data.

Where it should sit

Across the photo and the key details, not in an empty corner. A watermark in a blank margin can simply be cropped off. It should still let the recipient read your name and number, because they need to, so aim for a mark that is clearly visible without covering anything completely.

A diagonal line of text across the middle of the card does this well. For a copy that will be kept on file for a long time, repeating the text across the whole page is harder still to crop around.

Step by step

1. If your copy is a photo or scan image, turn it into a PDF first with Image to PDF. It takes JPG, PNG and WebP.
2. Open Watermark PDF and choose the PDF.
3. Choose Text and type your wording into Watermark text.
4. Untick "Place behind the page content". A scanned ID is one large picture covering the page, and the mark belongs on top of it.
5. Set Opacity between about 30% and 40%. The default of 25% suits plain text pages and can be too faint over a photo.
6. Set the Angle: Diagonal (45°) is the usual choice. Tick Repeat across the whole page if you want the text tiled.
7. Press Apply watermark, then Save Changes, then Download PDF.

Then open the downloaded file and check that the mark really crosses the photo and the details, and that everything the recipient needs is still readable.

Use text, not an image

Watermark PDF can also place an image, such as a logo. For an ID copy, use text. A text watermark can say exactly who the copy is for and when it was sent, which is the whole point, and it lets the details underneath show through at the opacity you choose.

Making it harder to strip

A watermark added to a PDF is drawn onto the page, but Latin-alphabet text in it stays real text. Someone with a PDF editor and some patience could find it and delete it.

If you want the mark fused into the picture itself, do one more round trip:

1. Convert the watermarked PDF to an image with PDF to Image, choosing PNG.
2. Turn that image back into a PDF with Image to PDF.

Now the watermark and the ID are the same pixels, and removing one means repainting the other. The cost is resolution: pages are rendered at 150 DPI, which usually keeps an ID card readable but is not a copy for professional printing.

What a watermark does not do

• It does not make the copy secret. It is still your document, with your details on it. Send it by the most private route the recipient offers.
• It does not stop someone photographing the original. It protects the copy you send, not the card in your wallet.
• Some checks need an unmarked copy. A bank or government office verifying your identity may ask for an unmarked copy, or may want to see the original document itself. Ask before sending if you are not sure, rather than having an application sent back.

Other precautions worth taking

• Send only the pages needed. A passport PDF with every visa page in it is more than a landlord needs. Delete Pages removes the rest.
• Hide what they do not need. If the recipient only needs your name and photo, Redact PDF can remove other numbers from the file itself, not just cover them. Ask first; some checks need the full number.
• Keep your own unmarked master somewhere safe, and make a fresh marked copy for each recipient.