Irish linen is linen produced in Ireland. Linen has been spun and woven in Ireland for centuries. Linen is made from the flax plant, which was grown in Ireland for many years before advanced agricultural methods and more suitable climate led to the concentration of flax cultivation in northern Europe (Most of the world crop of quality flax is now grown in Northern France, Belgium and Holland). Today flax for Irish Linen yarn is imported from France, Belgium and Holland. It is bought by spinners who produce yarn and this, in turn, is sold to weavers (or knitters) who make fabric.

Classification as Irish

Irish Linen yarn is defined as yarn which is spun in Ireland from 100% flax fibres. Irish Linen fabric is defined as fabric which is woven in Ireland from 100% linen yarns. The yarns do not necessarily have to come from an Irish spinner and sometimes come from Italy, France and the Far East. Products made from Irish Linen fabric may be labelled "Irish Linen" with the Irish Linen Guild trademark. The Irish Linen Guild is the official promotional body for the industry and was formed in 1928.

Goods made from Irish Linen fabric (including clothes and table or bedlinen) are often shipped to garment manufacturing plants across the world where they are made up to designers' or retailers' specifications.

Because of Country of Origin laws, these products may end up being labelled Made in X whereby X is the country they were made up in. Consumers are often confused by this, especially if the product is also labelled "Irish Linen". The linen is "Irish Linen" if it is woven in Ireland – regardless of where the product is made up.

The Irish Linen Guild’s labels and swing tags stress this to avoid confusion for consumers and retailers.