Retro Circles Background 4@2X #421
 Dark  CC 0

Retro Circles Background 4

Source GDJ

 More Textures
Background pattern 227 (colour 3) #2312
 Pink  CC 0

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

Colorful Floral Pattern Background 8 #230
 Fabric  CC 0

PDP

Source GDJ

Transparent Square Tiles #298
 Grid  CC BY-SA 3.0

The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.

Source Nathan Spady

Background pattern 225 (colour 6) #2322
 Brown  CC 0

Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

Background pattern green #1947
 Green  CC 0

To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Xv@2X #315
 Paper  CC BY-SA 3.0

Floral patterns will never go out of style, so enjoy this one.

Source Lasma

Soft Circle Scales@2X #114
 Light  CC BY-SA 3.0

Japanese looking fish scale pattern.

Source Ian Soper

Exclusive Paper@2X #24
 Light  CC BY-SA 3.0

Paper pattern with small dust particles and 45-degree strokes.

Source Atle Mo

Background pattern 223 (colour 2) #2352
 Blue  CC 0

Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

Background pattern 203 (colour 2) #2485
 Green  CC 0

A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Retro Circles Background 8 #435
 Dark  CC 0

Retro Circles Background 8

Source GDJ