This one is something special. I’d call it a flat pattern, too. Very well done, sir!
Source GetDiscount
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
A free black metallic background pattern. Here's a new pattern I made that looks metallic.
Source V. Hartikainen
A simple but elegant classic. Every collection needs one of these.
Source Christopher Burton
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
Drawn in Paint.net and vectorised in Vector Magic
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Remixed from a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
Prismatic Groovy Concentric Background 3 No Black
Source GDJ
A seamless canvas texture for using as background on websites. Colored in pale tones of brown.
Source V. Hartikainen
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
This seamless light brown background texture resembles a wallpaper with vertical stripes. One way to use it is as a tiled background on web sites.
Source V. Hartikainen
This is the remix of "Colorful Floral Pattern Background 3" uploaded by "GDJ". Thanks.
Source Yamachem
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin