Transparent Square Tiles@2X #299
 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

 More Textures
Background pattern 215 (colour 2) #2370
 Blue  CC 0

A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.

Source Firkin

Background pattern 226 #2321
 Brown  CC 0

A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Dark Steel Grid Background Pattern #1081
 Metal  CC BY-SA 3.0

Here's a dark background pattern that contains a steel grid pattern as a texture. Use it as a website background or for other purposes. It's free!

Source V. Hartikainen

Vintage tile background #2248
 Brown  CC 0

A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Ravenna #354
 Wall  CC BY-SA 3.0

I guess this is inspired by the city of Ravenna in Italy and its stone walls.

Source Sentel

"Dark Metal Plate", Web Background #1084
 Metal  CC BY-SA 3.0

A dark metal plate with an embossed grid pattern and a bit of rust. Here's a dark metal plate texture for use as a tiled background on web pages.

Source V. Hartikainen

Fake Brick@2X #359
 Dark  CC BY-SA 3.0

Black, simple, elegant, and useful.

Source Marat

Prismatic Abstract Geometric Background 2 #268
 Noise  CC 0

Prismatic Abstract Geometric Background 2

Source GDJ

Fabric pattern 2 (colour 2) #2395
 Fabric  CC 0

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

Joined spirals pattern #2482
 Yellow  CC 0

The starting point for this was drawn on the web site steamcoded.org/PolyskelionMaker.svg

Source Firkin

Fabric pattern #2402
 Fabric  CC 0

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

Dark Mosaic #121
 Dark  CC BY-SA 3.0

Small dots with minor circles spread across to form a nice mosaic.

Source John Burks

Floral pattern 14 #1754
 Yellow  CC 0

The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin