A formal will has many requirements under the law. When you write a letter that describes what you want done with your personal property, this may serve as an informal, or holographic, will. However, even your letter must meet certain requirements, and even so, many states will refuse to recognize a holographic will. If you have the time and ability to make a formal will, it has a better chance of passing probate.
Making Formal Wills
If you try to use a letter as a will, the best-case scenario is to make sure that the letter meets all the formalities of a formal will. While the specifics of state will execution law vary, all states require that the will be signed by you, the testator. You must also find two witnesses -- three in some states -- who will watch you sign the will, and then sign it themselves as proof. Under most states' laws, all witnesses must be in each other's presence when they sign, and many states require that the witnesses be disinterested, meaning that they don't expect to benefit from your will. If one of your witnesses will benefit, his signing the will generally means that he gives up his right to anything you leave him.
If your letter doesn't meet the requirements of a formal will, it may still qualify as a holographic, or handwritten, will. More than half of U.S. states recognize the holographic will, but requirements vary widely by each state's probate code. Generally, the entire letter must be handwritten and must include the date and your signature in your own handwriting as well. No states accept an electronic signature on a holographic will. Note that for a court to consider your letter as a holographic will, it must contain clear language showing that you mean for the letter to serve as a last will and testament.
Capacity to Execute
Whether you mean your letter to serve as a formal or informal will, no court will probate it unless you had the mental capacity to execute the will. This means that at the time of writing the letter, you must be capable of understanding the property involved, the fact that you're creating a will and who your descendants are. The last requirement is especially true if you plan to leave your property to a non-relative; the court must feel reasonably certain that you knew what you were doing. Most states require that you be at least 18 years old when you write the letter, although some states allow wills made by a younger person who is married, a member of the military or financially independent from his parents.
While there is no legal problem with leaving your property to a non-relative in a will, you should know that if your letter fails to meet your state's requirements for either a formal or holographic will, the property referenced in the letter will probably go to your relatives. When your property isn't dealt with in a will, trust or other estate planning scheme, a legal system called intestate succession takes over. This system distributes your property to your descendants if you have any. If not, depending on your state, the property may go to your parents, siblings or sibling's children. If you have absolutely no living relatives, the property will probably go to the state.
Erika Johansen is a lifelong writer with a Master of Fine Arts from the Iowa Writers' Workshop and editorial experience in scholastic publication. She has written articles for various websites.