Organic fiber includes cotton, wool, hemp, flax (linen), and other natural fibers grown according to national organic standards without the use of toxic and persistent pesticides, synthetic fertilizers, or genetic engineering. For a textile to qualify as organic, one must also address all the post-harvest processing stages (including spinning, knitting, weaving, dyeing and manufacturing).

Apart from these materials being completely natural and safe to wear, they are also more susceptible to speedier biodegradation when compared to their synthetic counterparts.