Prismatic Geometric Pattern Background
Source GDJ
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
Might not be super subtle, but quite original in its form.
Source Alex Smith
Prismatic Snowflakes Pattern No Background
Source GDJ
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
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
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
A black tile-able background with paper-like texture.
Source V. Hartikainen
I love these crisp, tiny, super subtle patterns.
Source Badhon Ebrahim
Prismatic Basic Pattern 2 No Background
Source GDJ
Abstract Tiled Background Extended 10
Source GDJ
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
A seamless pattern based on a tile that can be achieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
This light yellow background pattern consists of an irregular pattern of spots. Here's a light background pattern with yellowish tint.
Source V. Hartikainen
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
Dark wooden pattern, given the subtle treatment. based on texture from Cloaks.