This article covers the workflow for Lightroom Classic. Using Lightroom desktop? See Add Graphical and Signature Watermark.
In any module, choose Edit > Edit Watermarks (Windows) or Lightroom Classic > Edit Watermarks (macOS).
In the Watermark Editor dialog box, select a Watermark Style: Text or Graphic.
(Text watermark) Type the text under the preview area and specify Text Options: font, style, alignment, color, and drop shadow. OpenType fonts are not supported.
(Graphic watermark) Click Choose in the Image Options pane and then navigate to and choose the PNG or JPEG that you want to use.
Adjust the level of transparency of the watermark.
Proportional scales the watermark larger or smaller. Fit sizes the watermark across the width of the photo. Fill sizes the watermark to fill the height and width of the photo.
Repositions the watermark horizontally or vertically in the photo.
Anchor the watermark to one of nine anchor points in the photo, and rotate the watermark left or right.
If you have trouble seeing the watermark on final images, experiment with a larger size or different position on the photo.
For instructions on how to apply copyright watermarks to photos, see: