Seamless tile drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Zero CC tileable yellow craft paper; scanned and made by me. CC0
Source Sojan Janso
Super simple but very nice indeed. Gray with vertical stripes.
Source Merrin Macleod
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
This is a hot one. Small, sharp and unique.
Source GraphicsWall
A free seamless background image with a texture of dark red "canvas". It should look very nice on web sites.
Source V. Hartikainen
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Not the Rebel alliance, but a dark textured pattern.
Source Hendrik Lammers
Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
Prismatic Chevrons Pattern 5 With Background
Source GDJ
Oh yes, it happened! A pattern in full color.
Source Atle Mo
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Awesome name, great pattern. Who does not love space?
Source Nick Batchelor
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Prismatic Groovy Concentric Background
Source GDJ
Here's a tile-able wood background image for use in web design.
Source V. Hartikainen
Derived from an image that was uploaded to Pixabay by starchim01
Source Firkin
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall