A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Same classic 45-degree pattern, dark version.
Source Luke McDonald
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Hexagonalist Pattern No Background
Source GDJ
The image depicts a seamless pattern which was made using stripe-like things including borders.I used OCAL cliparts called "Blue Greek Key With Lines Border" uploaded by "GR8DAN" and "daisy border" uploaded by "johnny_automatic".Thanks.
Source Yamachem
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
Prismatic Abstract Background Design No Black
Source GDJ
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
Zero CC tileable wood texture, made by me procedurally in Neo Texture Edit.
Source Sojan Janso
To get the repeating unit, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
One can never have too few rice paper patterns, so here is one more.
Source Atle Mo
A pattern derived from part of a fractal rendering in Paint.net.
Source Firkin
A background pattern with blue on white vertical stripes.
Source V. Hartikainen
ZeroCC tileable stone texture, edited from pixabay. CC0
Source Sojan Janso
Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
Awesome name, great pattern. Who does not love space?
Source Nick Batchelor
Alternative colour scheme for the original floral pattern.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers