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
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
Pattern that came out of playing with the 'slinky' plug-in for Paint.net
Source Firkin
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
Prismatic Groovy Concentric Background 2
Source GDJ
Real snow that tiles, not easy. This is not perfect, but an attempt.
Source Atle Mo
This one could be the shirt of a golf player. Angled lines in different thicknesses.
Source Olivier Pineda
Here's a seamless brown cork board background texture. Feel free to download or reshare if you like.
Source V. Hartikainen
This is a grid, only it’s noisy. You know. Reminds you of those printed grids you draw on.
Source Vectorpile
A classic dark tile for a bit of vintage darkness.
Source Listvetra
Fix and cc0 to get the tile this is based on.
Source SliverKnight
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The following free background pattern has glossy diagonal stripes as a texture to it, and it's colored in a light blue gray color. This background pattern is suitable for using in web design or any other graphic design projects. This applies to all background patterns here.
Source V. Hartikainen
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
Alternative colour scheme. 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 bit of scratched up grayness. Always good.
Source Dmitry
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Lovely pattern with splattered vintage speckles.
Source David Pomfret
ZeroCC tileable stone texture, edited from pixabay. CC0
Source Sojan Janso
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Oh yes, it happened! A pattern in full color.
Source Atle Mo
Prismatic Hexagonalist Pattern No Background
Source GDJ