What does the watermark on a check look like?

Hold the check at a shallow angle to a light, around 45 degrees, and look at the back. If there is a watermark, that is where it shows: a faint word or logo that disappears the moment you look at the paper straight on. Check stock often prints a note about it on the back, along the lines of the back of this document contains an artificial watermark.

Artificial is the industry's word, not a warning

An artificial watermark is printed. A true watermark is not.

A true watermark is formed at the mill, by varying the thickness of the wet fibers before the paper dries. The image is part of the sheet, so it shows when you hold the page up to a light, with soft edges and no texture you can feel. An artificial one is printed on the back in transparent or coin-reactive ink and only shows at an angle, or when you rub it with the edge of a coin. True watermarked paper exists and turns up on premium and high-security check stock. The printed version is cheaper, which is why it is the one most people find.

Why the angle matters

Both kinds defeat the same attack. A copier or a scanner photographs the page flat, at 90 degrees, which is the one angle the printed mark does not show at. A counterfeit run off from a scan comes out without it, so the absence is the tell. A true watermark fails to copy for a different reason: it is paper thickness, and a copier only sees ink.

What neither one tells you is whether the check is any good. It says the paper came from a check printer. It says nothing about the account behind it, the balance, or the signature. And once the check clears as an image, nobody is holding anything at an angle.

Not related to a digital watermark

The mark in an AI-generated image, or the invisible characters in a block of text, share the name and nothing else. Watermarking means four different things, and the one on your check is the oldest of them.