A trust instrument (also sometimes called a deed of trust, where executed by way of deed) is an instrument in writing executed by a settlor used to constitute a trust. Trust instruments are generally only used in relation to an inter vivos trust; testamentary trusts are usually created under a will.
Although in most legal systems there are certain formalities associated with settling a trust, most legal systems impose few, if any, structures on the trust instrument itself. Historically, the concept of a trust is the intervention of the courts of equity to prevent a legal owner treating the property as beneficially his own; provided that state of affairs exists, a trust arises notwithstanding any lack of formality in relation to the form of the trust instrument.
However, notwithstanding the flexible approach taken by the law, characteristically the legal profession has taken an extremely formalised approach to trust instruments. Not only are they invariably always executed under seal as a deed, but frequently the initial trust fund (usually a nominal amount), will actually be physically affixed to the trust instrument itself to prove that the initial trust property was transferred.
Some slightly unusual practices have arisen in relation to the drafting of trust instruments which, again, are rigidly adhered to by professionals in many common-law countries (although not the U.S.A.). For example, trust deeds will generally avoid all punctuation (including full stops) - to avoid confusion, all new sentences commence with a new, numbered, paragraph. Dates, including years, are conventionally spelled out in words rather than using figures.
Part of the over-formalisation which attends the creation of trusts is justified by the significant tax implications which may follow if a trust were to be subsequently held to be void, as most professionally drafted trust instruments are prepared as a part of tax mitigation schemes.
Most jurisdictions do not require trust instruments to be publicly filed (in contrast to wills). But in many jurisdictions they are subject to stamp duty.
The provisions of a trust instrument will vary according to the type of trust, and the nature of the trust property.