To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A free seamless background texture that looks like a brown stone wall.
Source V. Hartikainen
Tiny little flowers growing on your screen. Nice, huh?
Source Themes Tube
Prismatic Groovy Concentric Background
Source GDJ
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A repeating background of beige paper with vintage look. Repeats to infinity, as usual.
Source V. Hartikainen
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Basket Fibers, Basket Texture, Braid Background style CC0 texture.
Source 1A-Photoshop
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
This one resembles a black concrete wall when is tiled. It should look great, at least with dark website themes.
Source V. Hartikainen
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
One more brick pattern. A bit more depth to this one.
Source Benjamin Ward
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin