The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Sometimes you just need the simplest thing.
Source Fabricio
The name alone is awesome, but so is this sweet dark pattern.
Source Federica Pelzel
A background pattern with blue on white vertical stripes.
Source V. Hartikainen
Another fairly simple design drawn in Paint.net and vectorized in Inkscape.
Source Firkin
Derived from an image that was uploaded to Pixabay by TheDigitalArtist
Source Firkin
This one is super crisp at 2X. Lined paper with some dust and scratches.
Source HQvectors
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins
A bit strange this one, but nice at the same time.
Source Diogo Silva
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
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
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).
Source V. Hartikainen
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
Geometric triangles seem to be quite hot these days.
Source Pixeden
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin