Allodial title is a concept in some systems of property law. It describes a situation where real property (land, buildings and fixtures) is owned free and clear of any encumbrances, including liens, mortgages and tax obligations. Allodial title is inalienable, in that it cannot be taken by any operation of law for any reason whatsoever.

In common legal use, allodial title is used to distinguish absolute ownership of land by individuals from feudal ownership, where property ownership is dependent on relationship to a lord or the sovereign. Webster's first dictionary (1825 ed) says allodium is "land which is absolute property of the owner, real estate held in absolute independence, without being subject to any rent, service, or acknowledgement to a superior. It is thus opposed to feud.

True allodial title is rare, with most property ownership in the common law world—primarily, the United Kingdom, the United States, Canada, Australia and New Zealand—described more properly as being in fee simple. In particular, land is said to be "held of the Crown" in England and Wales and the Commonwealth realms. In England, there is no allodial land, all land being held of the Crown; even in the United States most lands are not allodial, as evidenced by the existence of property taxes. Some of the Commonwealth realms recognise native title, a form of allodial title that does not originate from a Crown grant.

In France while allodial title existed before the French Revolution it was rare and limited to ecclesiastical properties and property that had fallen out of feudal ownership. After the French Revolution allodial title became the norm in France and other civil law countries that were under Napoleonic legal influences. Interestingly Quebec adopted a form of allodial title when it abolished feudalism in the mid-nineteenth century making the forms of ownership in Upper and Lower Canada remarkably similar in substance.

Property owned under allodial title is referred to as allodial land, allodium, or an allod.