What the document is actually for, and why the absence of legal force is a feature. Every other document in an estate plan is constrained by what a court will enforce. That constraint is what makes a will useful and also what makes it a bad place to explain yourself: a sentence added to a will to justify an unequal division is a sentence a disappointed heir can read, quote and litigate around. An ethical will has no such exposure, because there is nothing in it to attack. It can say that one child received more because they carry a disability, or less because they received help earlier, or that a business was left to the sibling who worked in it, in the writer's own words and without drafting consequences.
The typical contents are narrower than the name suggests. There is no standard length and no standard form; what these documents tend to contain is some mixture of: the beliefs the writer holds and where they came from; what they learned from particular failures; family history that would otherwise be lost with them, including the ordinary details nobody writes down; specific gratitude, addressed to named people; things they wish they had said; and their hopes for what the family does next, offered as hopes rather than as instructions. Some include an explanation of the estate plan itself. Some are recorded rather than written, as audio or video, which changes nothing legally and is often easier for the writer.
The distinction from a letter of instruction is subject, not form. Both documents are informal, unwitnessed and unenforceable. A letter of instruction is the practical map: where the will is kept, which accounts exist at which institutions, who the accountant is, what subscriptions renew. An ethical will contains none of that and makes no attempt to help anybody administer anything. The two are frequently bundled in the same envelope and are still doing different jobs, and confusing them tends to produce a document that does neither well.
The one real hazard is presentational, and it is easy to avoid. A document headed "will," stored with the will, unsigned and undated, invites exactly the wrong reading. A survivor who finds it may treat it as testamentary and act on it, or, worse, may treat an expressed hope as a direction that conflicts with the actual will and delay the estate while somebody works out which document governs. Three habits close the gap: title it something that cannot be mistaken for a testamentary instrument, say in its first line that it has no legal effect and is not intended to change anything in the will, and date it. Where the writer's intention really is to direct who gets which belongings, that is a different mechanism entirely and belongs in the will or in the separate tangible-property list some state probate codes recognize. It is worth being precise about why: a document is judged by what it says and whether it satisfies that state's execution formalities, not by the heading at the top of it. A handwritten and signed page that does dispose of property is not saved from being tested as a will by having been called something else, and in a state that admits a holographic will it might well be one. The page on the holographic will covers that case.
A word on timing, because the document has one unusual property. Unlike the rest of an estate plan, an ethical will loses nothing by being read while the writer is alive. Some people give it to their family directly, which removes the possibility of it being misread as an instruction and lets the conversation happen with the writer in the room. Others write successive versions over decades. Since nothing about it is filed, witnessed or registered, there is no cost to either approach and no version that has to be formally revoked.
