A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
ZeroCC tileable beechwood wood texture, generated in Neo Texture Edit by me. CC0
Source Sojan Janso
A new take on the black linen pattern. Softer this time.
Source Atle Mo
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
White circles connecting on a light gray background.
Source Mark Collins
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
A cute x, if you need that sort of thing.
Source Juan Scrocchi
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
Prismatic Abstract Geometric Background 4
Source GDJ
Prismatic Polyskelion Pattern No Background
Source GDJ
A dark one with geometric shapes and dotted lines.
Source Mohawk Studios
No idea what Nistri means, but it’s a crisp little pattern nonetheless.
Source Markus Reiter
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern of leopard skin. It should look nice as a background element on web pages.
Source V. Hartikainen
The image is a seamless pattern which is derived from a vine .Consequently, the vine got like dots via vectorization.The original vine is here:jp.pinterest.com/pin/500744052301410188/
Source Yamachem