The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
Abstract Tiled Background Extended 11
Source GDJ
Adapted from an image that was uploaded to Pixabay by Anerma.
Source Firkin
Scanned some rice paper and tiled it up for you. Enjoy.
Source Atle Mo
Seamless pattern inspired by a drawing on Pixabay. To get the tile this is formed from, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Medium gray fabric pattern with 45-degree lines going across.
Source Atle Mo
Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Floral patterns might not be the hottest thing right now, but you never know when you need it!
Source Lauren
This is the remix of "Strawberry Pattern Background" uploaded by "GDJ". Thanks. I realigned strawberries so as to get seamless and changed the BG color.
Source Yamachem
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Light honeycomb pattern made up of the classic hexagon shape.
Source Federica Pelzel
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media